Journal articles: '2-diamina'

1

Zaini, Mahirah, Rohah A. Majid, and Hossein Nikbakht. "Modification of Montmorillonite with Diamine Surfactants." Applied Mechanics and Materials 695 (November 2014): 224–27. http://dx.doi.org/10.4028/www.scientific.net/amm.695.224.

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Sodium montmorillonite (Na-MMT) was modified with various type of diamine surfactants. The modification imparts hydrophobic characters of MMT, thus enhancing its compatibility and dispersibility in polymer matrix. In this research, pristine MMT was modified with three types of diamine surfactants, namely, 1,3 diaminopropane (DAP), 1,8 diamino octane (DAO) and 1,5 diamino-2-Methyl pentane (DAMP). These diamines have different molecular structures where DAP has a short linear structure, DAO has eight carbons while DAMP has a methyl branch on its backbone. The modification was carried via cationic exchange process. X-ray diffraction (XRD) analysis showed the enhancement of d-spacing of MMT galleries and the formation of intercalated structure with the incorporation of diamines. Overall, type of diamines did not give significant effect on the d-spacing values with DAMP-MMT exhibited a slightly higher d-spacing at 13. 36 Å. The presence of methyl branch on the DAMP backbone was thought provide more spacing for the diamine to intercalate through the MMT gallery. Meanwhile, the detection of –NH bending amine group at 1470 cm-1 on the Fourier infrared (FTIR) spectra, corresponding to the free surfactant tail, had confirmed the successfulness of cationic exchange reaction between the diamines and MMT surface.

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2

Acosta Beltrán, Sherly Catherin, Carlos E. Daza, and Carolina Blanco Jiménez. "Catalizadores tipo zinc(salen) y su aplicación en la copolimerización entre óxido de limoneno y CO2." Scientia et technica 24, no. 2 (June 30, 2019): 275. http://dx.doi.org/10.22517/23447214.16311.

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En este trabajo se lleva a cabo la síntesis y caracterización de catalizadores tipo salen con Zn, los cuales son obtenidos mediante reacción de condensación entre una 1,2-diamina y 3,5-diterc-butilsalicilaldehído en presencia de acetato de zinc. Se obtuvieron rendimientos del 86% en la síntesis del catalizador Zn-salen-1, 60% para Zn-salen-2 y 70% para Zn-salen-3. Estos catalizadores fueron usados en la reacción de acoplamiento de óxido de limoneno con CO2. Los mejores resultados en términos de conversión (20%) se evidenciaron cuando el sistema catalítico Zn-salen-2/NBuI se evaluó usando 20 bar de CO2, 40°C durante 24 h. En todos los casos studiados, la reacción demostró ser completamente selectiva hacia la formación del policarbonato de limoneno. No se encontró dependencia significativa de la presión de CO2 en la determinación de la actividad del sistema catalítico examinado.

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3

Herbig, Marcus, Henrik Scholz, Uwe Böhme, Betty Günther, Lia Gevorgyan, Daniela Gerlach, Jörg Wagler, Sandra Schwarzer, and Edwin Kroke. "New cyclic and spirocyclic aminosilanes." Main Group Metal Chemistry 44, no. 1 (January 1, 2021): 51–72. http://dx.doi.org/10.1515/mgmc-2021-0007.

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Abstract New cyclic and spirocyclic aminosilanes were synthesised using ethylenediamine, 2-aminobenzylamine, 1,8-diaminonaphthalene, o-phenylenediamine, and trans-cyclohexane-1,2-diamine as starting material. These diamines were converted into aminosilanes using silicon tetrachloride and dimethyldichlorosilane directly and via the N,N’-bis(trimethylsilylated) amino derivatives. 15 new compounds of the type (diamino)(SiMe3)2, (diamino)2Si, (diamino)SiMe2, and (diamino)SiCl2 have been prepared. The formation of two cyclotrisilazane derivatives was observed starting from (N,N’-2-aminobenzylamino)dichlorosilane by trimerisation. All synthesised compounds have been characterised with NMR-, Raman-, or IR-spectroscopy, mass-spectrometry, and boiling or melting point. Single-crystal X-ray structure analyses of several derivatives have been performed. The degree of substitution with trimethylsilyl groups in the final compounds depends on the ring size of the spirocycles. It was shown with quantum chemical calculations on the M062X/6-31G(d) level that trimethylsilyl groups have a stabilising effect on 5-membered ring systems and a destabilising effect on 6-membered rings in these compounds.

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4

Ali, Dr Firyal M., and Haider H. Rashed. "Poly-Condensation of CDTA with Some Diamines." Journal of Petroleum Research and Studies 4, no. 1 (June 1, 2013): 58–70. http://dx.doi.org/10.52716/jprs.v4i1.89.

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In this research, new condensed polymers (A1-A8) were prepared by poly condensation between 1, 2-cyclohexyl diamine tetraacetic acid CDTA with different diamines such as 1, 6-Diamino hexane, Melamine, 3,3-,5,5--Tetramethyl benzidine, Benzidine and Cystine. These prepared chelate polymers could be used to remove heavy metals and toxic metal ions in many industrial processes as well as acting as sequestrate for metal ions. The all prepared polymers were characterized by 1H-NMR and FT-IR spectra. The thermal analyses (TGA, DSC) were studied, the intrinsic viscosities were calculated at 30 ˚C using Ostwald viscometer, and all physical properties were measured.

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5

Matsukizono, Hiroyuki, and Takeshi Endo. "Synthesis of Bi- and Trifunctional Cyclic Carbonates Based on Trimethylolpropane and Their Application to Networked Polyhydroxyurethanes." Journal of Materials Science Research 5, no. 3 (April 7, 2016): 11. http://dx.doi.org/10.5539/jmsr.v5n3p11.

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The reaction of trimethylolpropane (TMP) and diphenyl carbonate gives three types of TMP-based six-membered cyclic carbonates (TMPCs) via phosgene-free route. TMPC having one hydroxyl group (TMPC-OH) reacted with terephthaloyl chloride or trimesoyl chloride to give bifunctional (Ph-TMPC2) or trifunctional cyclic carbonate monomers (Ph-TMPC3), respectively. The ring-opening polyaddition of Ph-TMPC2 and conventional diamines efficiently proceeded without the cleavage of ester bonds to afford linear polyhydroxyurethanes (PHUs) with well-controlled molecular weights and polydispersities via isocyanate-free route. Moreover, the polyaddition of Ph-TMPC2 and diamine at TMPC2/diamine feed ratio of 1.1 afforded PHUs having cyclic carbonate terminals, the hydroxyl side chains of which were easily reacted with acetic anhydride to give acetylated PHUs with cyclic carbonate terminals. On the other hand, the polyaddition at Ph-TMPC2/diamine feed ratio of 0.91 gave PHUs with amine terminals. The copolymerization of Ph-TMPC2, Ph-TMPC3 and diamine gives PHUs comprising covalently-bridged networked structures. After DMF solutions of Ph-TMPC2, Ph-TMPC3 and diamines were simply kept at 60 °C overnight, networked PHU films with well transparency were successfully fabricated. The PHU films prepared at different diamines showed similar transparency and thermal stability, while the mechanical properties were significantly affected by the methylene spacers of diamines.

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6

PEC, Pavel, and Ivo FRESORT. "1,4-Diamino-2-butyne as the mechanism-based pea diamine oxidase inhibitor." European Journal of Biochemistry 209, no. 2 (October 1992): 661–65. http://dx.doi.org/10.1111/j.1432-1033.1992.tb17333.x.

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7

Hawthorne, D. G., J. H. Hodgkin, M. B. Jackson, J. W. Loder, and T. C. Morton. "Preparation and characterization of some new diaminobisimides." High Performance Polymers 6, no. 4 (August 1994): 287–301. http://dx.doi.org/10.1088/0954-0083/6/4/001.

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A series of stable diaminobisimides (DABIs) has been prepared as alternatives to simple aromatic diamines for use in the preparation of condensation polymers. These DABIs were prepared by reacting two moles of an aromatic diamine with one mole of a dianhydride under conditions that minimize side reactions and the formation of oligomers. In many cases, the pure DABI consisting of two moles of the diamine and one mole of the dianhydride (i.e. the 2:1 product) can be obtained free of oligomers (i.e. the 3:2, 4:3 etc products). The studies have shown that the major factor determining the yield and purity of a DABI is the extent of conjugation between the two amino groups in the starting diamine: to a lesser extent steric effects in the diamines also influence the product composition. The reaction conditions necessary to produce these new DABIs are described together with extensive characterization of these materials by FTIR,1H and 13C NMR and gel permeation chromatography. The results indicate that pure DABIs are more manageable materials than the impure. insoluble materials previously described in the literature and can be used successfully to produce useful high-temperature stable polymers.

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8

Bermejo, Manuel R., Rocío Carballido, M. Isabel Fernández-García, Ana M. González-Noya, Gustavo González-Riopedre, Marcelino Maneiro, and Laura Rodríguez-Silva. "Synthesis, Characterization, and Catalytic Studies of Mn(III)-Schiff Base-Dicyanamide Complexes: Checking the Rhombicity Effect in Peroxidase Studies." Journal of Chemistry 2017 (2017): 1–10. http://dx.doi.org/10.1155/2017/5465890.

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The condensation of 3-methoxy-2-hydroxybenzaldehyde and the diamines 1,2-diphenylendiamine, 1,2-diamine-2-methylpropane and 1,3-propanediamine yielded the dianionic tetradentate Schiff base ligands N,N′-bis(2-hydroxy-4-methoxybenzylidene)-1,2-diphenylendiimine (H2L1), N,N′-bis(2-hydroxy-4-methoxybenzylidene)-1,2-diamino-2-methylpropane (H2L2) and N,N′-bis(2-hydroxy-4-methoxybenzylidene)-1,3-diaminopropane (H2L3) respectively. The organic compounds H2L1 and H2L2 have been characterized by elemental analysis, IR, 1H and 13C NMR spectroscopies and mass spectrometry electrospray (ES). The crystal structure of H2L2 in solid state, solved by X-ray crystallography, is highly conditioned in the solid state by two N-H•••N intramolecular interactions. The synthesis of three new manganese(III) complexes 1–3, incorporating these ligands, H2L1–H2L3, and dicyanamide (DCA), is reported. The complexes 1–3 have been physicochemically characterized by elemental analysis, IR and paramagnetic 1H NMR spectroscopy, ESI mass spectrometry, magnetic moment at room temperature and conductivity measurements. Complex 1 has been crystallographically characterized. The X-ray structure shows the self-assembly of the Mn(III)-Schiff base-DCA complex through µ-aquo bridges between neighbouring axial water molecules and also by π-π stacking interactions, establishing a dimeric structure. The manganese complexes were also tested as peroxidase mimics for the H2O2-mediated reaction with the water-soluble trap ABTS, showing complexes 1-2 relevant peroxidase activity in contrast with 3. The rhombicity around the metal ion can explain this catalytic behaviour.

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9

Yaramapa, Hari Babu, Cirandur Suresh Reddy, Venugopal Maralla, and Pedaiahgari Vasugovardhana Reddy. "New 2-aryloxy Macroheterocyclic Phosphates." Journal of Chemical Research 2005, no. 9 (September 2005): 587–89. http://dx.doi.org/10.3184/030823405774308880.

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A new class of phosphorus macroheterocycles (4a–j) has been synthesised in two steps. The reaction of 1 mole of 3,4-diamino-1,2,5-oxadiazole (1) with 2 moles of aqueous formaldehyde gave a Schiff's base which subsequently underwent addition with 2 moles of 4-t-butylphenol in 1,4-dioxane, afforded N,N-bis-(5-t-butyl-2-hydroxybenzyl)furazan-3,4-diamine (2). Cyclisation of 2 in situ with various substituted aryl phosphorodichloridates (3a–j) in the presence of Et3N in THF afforded 13-membered macroheterocycles (4a–j) containing P, N, O and C in good yields.

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10

He, Zuwen, Durgesh V. Nadkarni, Lawrence M. Sayre, and Frederick T. Greenaway. "Mechanism-based inactivation of porcine kidney diamine oxidase by 1,4-diamino-2-butene." Biochimica et Biophysica Acta (BBA) - Protein Structure and Molecular Enzymology 1253, no. 1 (November 1995): 117–27. http://dx.doi.org/10.1016/0167-4838(95)00158-q.

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11

Wang, Xian-Shan, Yoshikazu Takahashi, Masayuki Lijima, and Eiichi Fukada. "Low-temperature piezoelectric and dielectric properties of aromatic polyureas prepared by vapour deposition polymerization." High Performance Polymers 7, no. 3 (June 1995): 293–301. http://dx.doi.org/10.1088/0954-0083/7/3/006.

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Thin films of aromatic polyurea were prepared by vapour deposition of a diisocyanate tmonomer and a diamine monomer. Three kinds of aromatic polyurea were synthesized by combining 4,4'-dipheny Lnethane diisocyanate (MDI) with 4,4'-diamino-3,3'-dimethyldiphenylmethane (MeMDA), 4,4'-diaminodiphenylether (ODA), and 4,4'-diamino-diphenylmethane (MDA). After poling, for example applying a field of 120 MV m -I at 210C for 10 min, these films acquired piezoelectric activity. The piezoelectric constant (13-26 x 10 3 C m' 2) and dielectric constant (3-4) were almost constant over a temperature range between -150C and 50 C. Infrared spectra observed for as-deposited, poled and annealed films indicated that CO and NH dipoles were oriented along the poling field and that hydrogen bonds were formed between adjacent molecular chains.

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12

Buxton, DP, GB Deacon, BM Gatehouse, IL Grayson, RJ Thomson, and DS Black. "Organoamidometallics. I. Syntheses of [N,N′-Bis(Polyfluorophenyl)Ethane-1,2-Diaminato(2-)]Platinum(II) Complexes by Decarboxylation." Australian Journal of Chemistry 39, no. 12 (1986): 2013. http://dx.doi.org/10.1071/ch9862013.

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Reaction of PtCl2(en) (en = ethane-1,2-diamine) with thallous pentafluorobenzoate in hot pyridine ( py ) or 4-methylpyridine ( mepy ) yields the [N,N′- bis (2,3,5,6-tetrafluorophenyl)ethane-1,2-diaminato(2-)]platinum(II) complexes, Pt[N(p-HC6F4)CH2]2( py )2 (1a) and Pt[N(p- HC6F4)CH2]2( mepy )2 (1b). The route to (1a) is considered to involve formation of [Pt(en)( py )2](O2CC6F5)2 (2), decarboxylation of (2) into Pt(NHCH2)2( py )2 (1c) and pentafluorobenzene, and nucleophilic attack of (1c) on C6F5H. Complex (1a) has also been prepared by decarboxylation of (2), reaction of PtI2(en) and TlO2CC6F5, and reaction of PtCl2(en), C6F5H, and TlO2CC6F4H-p in boiling pyridine. From reaction of PtCl2(en), TlO2CC6F4H-p, and the appropriate polyfluorobenzene (RF) in boiling pyridine or 4-methylpyridine, the organoamidoplatinum compounds Pt(NRCH2)2L2(R = C6F5, p-MeC6F4, p-ClC6F4, p-BrC6F4, p-IC6F4, 2,3,5-F3C6H2, or p-C6F5C6F4, L = py and R = C6F5, L = mepy ) have been prepared. Analogous reactions of PtCl2( pn )( pn = propane-1,3-diamine) give the complexes Pt[NR(CH2)3NR]( py )2 (R = C6F5 or p-HC6F4). Spectroscopic evidence for the structures is discussed. The polyfluorophenyl groups confer stability to water on ethane-1,2-diaminato(2-)platinum(II) complexes, and this is attributable to delocalization of non-bonded lone pairs from the amido nitrogens into the polyfluorophenyl rings.

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13

Knopf, Claudia, Jörg Wagler, Erica Brendler, Horst Borrmann, and Gerhard Roewer. "Novel Five- and Six-Membered Diazasilacycloalkanes: Synthesis, Structure and Properties." Zeitschrift für Naturforschung B 59, no. 11-12 (December 1, 2004): 1337–47. http://dx.doi.org/10.1515/znb-2004-11-1254.

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Abstract The reactions of N,N’-dimethylethylenediamine 1and N,N’-diphenylethylenediamine 2with equimolar amounts of 1,2-dichlorotetramethyldisilane 3give six-membered heterocycles. Fivemembered rings are formed in the reaction of the diamines 1and 2with 1,1,2,2-tetrachlorodimethyldisilane 4as well as with hexachlorodisilane 5. Whilst the conversions of the disilanes 3and 4with the diamine 2gave no products of a disproportionation reaction, the treatment of the disilane 4with the diamine 1and of the disilane 5with both diamines resulted in cyclic aminosubstituted monosilanes which originate from the disproportionation of 4and 5beside the expected five-membered cyclic disilanes. All compounds have been characterized by multi-nuclear NMR, IR and mass spectroscopy. In case of the N-phenylsubstituted compounds 6, 7and 9the crystal structures have been determined by X-ray diffraction analysis. Bis-[N,N’-diphenyl-2-methyl-1,3-diaza-2-silacyclopentane] 6crystallizes in the chiral orthorhombic space group P212121 (Z = 4). Both silaimidazolidine rings in 6show half chair conformation. All nitrogen atoms of this molecule are almost planarized (sum of angles: 356.3◦ at N1, 359.5◦ at N2, 356.7◦ at N3 and 357.5◦ at N4). Bis-[N,N’-diphenyl-2-chloro-1,3-diaza- 2-silacyclopentane] 7, resulting from the reaction of disilane 5with diamine 2, crystallizes in the orthorhombic space group Pbcn (Z = 4). Its nitrogen atoms are almost planar (sum of angles: 357.9◦ at N1, 356.7◦ at N2). N,N’-diphenyl-2,2,3,3-tetramethyl-1,4-diaza-2,3-disilacyclohexane 9crystallizes in the chiral monoclinic space group P21 (Z = 2) and shows a twisted conformation. One nitrogen atom has a trigonal planar environment (sum of angles: 359.9◦ at N1), while the angle sum of the second one indicates a trigonal pyramidal conformation (sum of angles at N2: 350.6◦).

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14

Beltz, Mark W., and Frank W. Harris. "Synthesis and properties of aromatic polyimides containing oxyalkylene linkages." High Performance Polymers 7, no. 1 (February 1995): 23–40. http://dx.doi.org/10.1088/0954-0083/7/1/003.

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A series of para-catenated aromatic diamines containing oxyalkylene linkages, i.e., i.2-bis(4-aminophenoxy)ethane, bis[2-(4-aminnophenoxy)ethyl]ether, 1,2-bis[24{4-aminio-phenoxy)ethoxyjethane and bis{2-[2A4-aminophenoxy)ethoxy]ethyllether were polymerized with 3,3',4.4'benzophenonetetracarboxylic dianhydride (BTDA) and pyromellitic dianhydride. The poly(amic acid)s obtained were imidized by both chemical and thermal methods. It was postulated that the incorporation of the flexible linkages in the polyimides' backbones would result in solubility in organic solvents and moderate glass transition temperatures (Tg) that would allow the polymers to be melt processed. However, the polyimides were insoluble and highly crystalline with melting points (Tm) above 400"C. In an attempt to disrupt the polymers' symmetry. mixtures of the diamines and 1,3-bis(3-aminophenoxy)benzene were polymerized with BTDA. The resulting copolymers were insoluble and semrnicrystalline with Tm values near 310C. A polyimide with similar properties was obtained by polymerizing a disubstituted diamine, 2,2-diethyl-t,3-bis(4-aminophenoxy)propane, with BTDA. A soluble polymer that could be melt processed was prepared from BTDA and a meta-catenated diamine containing an oxyalkylene linkage, bis[2-(3-aminophenoxy)ethyl)ether. The polymer had a strong Tg near 156 'C and a weak Tm near 240C.

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15

Alsaeedi, Mona S., Bandar A. Babgi, Magda H. Abdellattif, Abdesslem Jedidi, Mark G. Humphrey, and Mostafa A. Hussien. "DNA-Binding Capabilities and Anticancer Activities of Ruthenium(II) Cymene Complexes with (Poly)cyclic Aromatic Diamine Ligands." Molecules 26, no. 1 (December 26, 2020): 76. http://dx.doi.org/10.3390/molecules26010076.

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Ruthenium(II) arene complexes of the general formula [RuCl(η6-p-cymene)(diamine)]PF6 (diamine = 1,2-diaminobenzene (1), 2,3-diaminonaphthalene (2), 9,10-diaminophenanthrene (3), 2,3-diaminophenazine (4), and 1,2-diaminoanthraquinone (5) were synthesized. Chloro/aqua exchange was evaluated experimentally for complexes 1 and 2. The exchange process was investigated theoretically for all complexes, revealing relatively fast exchange with no significant influence from the polycyclic aromatic diamines. The calf thymus DNA (CT-DNA) binding of the complexes increased dramatically upon extending the aromatic component of the diamines, as evaluated by changes in absorption spectra upon titration with different concentrations of CT-DNA. An intercalation binding mode was established for the complexes using the increase in the relative viscosity of the CT-DNA following addition of complexes 1 and 2. Theoretical studies showed strong preference for replacement of water by guanine for all the complexes, and relatively strong Ru–Nguanine bonds. The plane of the aromatic systems can assume angles that support non-classical interactions with the DNA and covalent binding, leading to higher binding affinities. The ruthenium arenes illustrated in this study have promising anticancer activities, with the half maximal inhibitory concentration (IC50) values comparable to or better than cisplatin against three cell lines.

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16

Pitarch López, Jesús, Frank W. Heinemann, and Andreas Grohmann. "The Zinc Aqua Complex of a Tetrapodal Pentaamine Ligand and its Reactivity towards Carbon Dioxide." Zeitschrift für Naturforschung B 59, no. 11-12 (December 1, 2004): 1600–1604. http://dx.doi.org/10.1515/znb-2004-11-1233.

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In the context of derivatisation studies of the pentaamine ligand 2,6-C5H3N[CMe(CH2NH2)2]2 (2-(6-(1,3-diamino-2-methylpropan-2-yl)pyridin-2-yl)-2-methylpropane-1,3-diamine, 1), we explored its zinc(II) coordination chemistry. With ZnBr2 in hot aqueous ethanol, in the absence of Lewis acid, the aqua complex [Zn(1)(H2O)]Br2 (2) is obtained, in which the pentaamine ligand acts as a square-pyramidal coordination cap. Single crystal structure data for the dihydrate of 2 are reported. In methanol solution, the complex is reactive towards carbon dioxide, and spectroscopic data (IR, 13C NMR) indicate the reversible formation of the dinuclear methyl carbonate complex [(Zn(1))2(μ2-(η1-O,η1-O)O2COCH3)]Br3.

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17

Ibrahim, Yusria R. "Synthesis of spiro(cyclohexa-diene-pyrazolo[1,5-a]pyrimidine-4-ylidene)-malononitrile derivatives." Journal of Chemical Research 2009, no. 8 (August 2009): 495–98. http://dx.doi.org/10.3184/030823409x466717.

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The reaction of 4-substituted aryldiazenyl-1 H-pyrazole-3,5-diamines with 7,7′,8,8′-tetra-cyanoquinodimethane gave 2-(2′,7′-diamino-6′-cyano-3′-(aryldiazenyl)-4′ H-spiro(cyclohexa[2,5]-diene-1,5′-pyrazolo[1,5- a]pyrimidine-4-ylidene) malononitriles in 63–79% yield, while, by reaction of 2-aminobenzimidazole with 7,7′,8,8′-tetracyanoquinodimethane, 2-(3′-amino-4′-cyano-6′ H-spiro-(cyclohexa[2′,5′]diene-1,5′-benzo( d)-imidazo[1,2- a]pyrimidine)-4-ylidene)malononitrile was formed in 71% yield. Rationales for these transformations are presented.

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18

Rossignoli, Monica, Paul V. Bernhardt, Geoffrey A. Lawrance, and Marcel Maeder. "Macrocycle Formation Through Carbon Acid - Formaldehyde Condensation Reactions of Bis(propane-1,2-diamine)- and Bis(2-methylpropane-1,2-diamine)-copper(II) Ions." Australian Journal of Chemistry 50, no. 6 (1997): 529. http://dx.doi.org/10.1071/c96219.

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The reaction of the bis(1,2-diamine)copper(II) complexes of racemic propane-1,2-diamine (pn) and 2-methylpropane-1,2-diamine (dmen) with formaldehyde and nitroethane in methanol under basic conditions yields minor macrocyclic condensation products in addition to the major acyclic products. Where C-pendant methyl groups on the pair of coordinated diamines are in cis dispositions, the first –NH–CH2–C(CH3)(NO2)–CH2–NH– ring formation occurs at amine pairs distant from these C-methyl substituents, and further reaction to yield a macrocycle is not observed. However, where the C-methyl substituents are in transdispositions, the chemistry proceeds to yield the macrocycle. Commencing with pn, trans-(6,13-diammonio-2,6,9,13-tetramethyl-1,4,7,10-tetraazacyclotetradecane)copper(II) perchlorate formed and crystallized in the space group P 21/n, with a9· 782(2), b 9·2794(6), c 17·017(4) Å, β 103·24(1)°. The copper ion is found in a square-planar environment, with the two methyl groups of the pn residues and the pairs of introduced pendant groups all in trans arrangements.

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19

Hasegawa, Masatoshi, and Tomoaki Hishiki. "Poly(ester imide)s Possessing Low Coefficients of Thermal Expansion and Low Water Absorption (V). Effects of Ester-linked Diamines with Different Lengths and Substituents." Polymers 12, no. 4 (April 8, 2020): 859. http://dx.doi.org/10.3390/polym12040859.

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A series of ester-linked diamines, with different lengths and substituents, was synthesized to obtain poly(ester imide)s (PEsIs) having improved properties. A substituent-free ester-linked diamine (AB-HQ) was poorly soluble in N-methyl-2-pyrrolidone at room temperature, which forced the need for polyaddition by adding tetracarboxylic dianhydride solid into a hot diamine solution. This procedure enabled the smooth progress of polymerization, however, accompanied by a significant decrease in the molecular weights of poly(amic acid)s (PAAs), particularly when using hydrolytically less stable pyromellitic dianhydride. On the other hand, the incorporation of various substituents (–CH3, –OCH3, and phenyl groups) to AB-HQ was highly effective in improving diamine solubility, which enabled the application of the simple polymerization process without the initial heating of the diamine solutions, and led to PAAs with sufficiently high molecular weights. The introduction of bulkier phenyl substituent tends to increase the coefficients of thermal expansion (CTE) of the PEsI films, in contrast to that of the small substituents (–CH3, –OCH3). The effects of ester-linked diamines, consisting of longitudinally further extended structures, were also investigated. However, this approach was unsuccessful due to the solubility problems of these diamines. Consequently, the CTE values of the PEsIs, obtained using longitudinally further extended diamines, were not as low as we had expected initially. The effects of substituent bulkiness on the target properties, and the dominant factors for water uptake (WA) and the coefficients of hygroscopic expansion (CHE), are also discussed in this study. The PEsI derived from methoxy-sustituted AB-HQ analog and 3,3′,4,4′-biphenyltetracarboxylic dianhydride achieved well-balanced properties, i.e., a very high Tg (424 °C), a very low CTE (5.6 ppm K−1), a low WA (0.41%), a very low CHE value (3.1 ppm/RH%), and sufficient ductility, although the 26 μm-thick film narrowly missed certification of the V-0 standard in the UL-94V test. This PEsI film also displayed a moderate εr (3.18) and a low tan δ (3.14 × 10−3) at 10 GHz under 50% RH and at 23 °C. Thus, this PEsI system is a promising candidate as a novel dielectric substrate material for use in the next generation of high-performance flexible printed circuit boards operating at higher frequencies (≥10 GHz).

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20

Hoang, D. Q., E. Ya Borisova, N. Yu Borisova, A. V. Krylov, N. A. Danilkin, and A. G. Samokhin. "SYNTHESIS, PREPARATIVE SEPARATION OF STRUCTURE ISOMERS AND PROPERTIES OF 2-(2-(DIALKYLAMINO)ETHYLAMINO)ETHANOLS OF ARYLALIPHATIC SERIES." Fine Chemical Technologies 12, no. 1 (February 28, 2017): 57–63. http://dx.doi.org/10.32362/2410-6593-2017-12-1-57-63.

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A method for the synthesis of 2-(2-(dialkylamino)ethylamino)ethanols based on the epoxide ring opening in styrene oxide by N,N-disubstituted ethylenediamines was developed. It is shown that the opening of the oxirane ring by diamines in 2-propanol at room temperature occurs mainly according to the Krasusky rule at the bond between the oxygen atom and the less substituted carbon atom. A mixture of two products with the predominance of the secondary diamino alcohol up to 82% was obtained. It was found that the separation of the products by distillation or recrystallization does not allow obtaining pure isomers. The mixture of isomers was converted into dihydrochlorides by dry HCl in dioxane and diethyl ether. Pure 2-(2-(dialkylamino)ethylamino)-1-phenylethanols and 2-(2-(dialkylamino)ethylamino)-2-phenylethanols were separated by the first fractional recrystallization of a mixture of diaminoalcohol dihydrochlorides from a mixed solvent followed by alkalization of the products with an aqueous sodium hydroxide solution. The diamino alcohols were characterized by FT-IR, 1H- and 13C-NMR and HRMS-ESI.

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21

Noyori, Ryoji, Masatoshi Koizumi, Dai Ishii, and Takeshi Ohkuma. "Asymmetric hydrogenation via architectural and functional molecular engineering." Pure and Applied Chemistry 73, no. 2 (January 1, 2001): 227–32. http://dx.doi.org/10.1351/pac200173020227.

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RuCl2 (phosphine) 2 (1,2-diamine) complexes, coupled with an alkaline base in 2-propanol, allows for preferential hydrogenation of a C=O function over coexisting conjugated or nonconjugated C=C linkages, a nitro group, halogen atoms, and various heterocycles. The functional group selectivity is based on the novel metal-ligand bifunctional mechanism. The use of appropriate chiral diphosphines and diamines results in rapid and productive asymmetric hydrogenation of a range of aromatic, hetero-aromatic, and olefinic ketones. The versatility of this method is manifested by the asymmetric synthesis of various biologically significant chiral compounds.

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22

Linhart, Igor, Petr Trška, and Václav Dědek. "Reaction of 3-chlorononafluoro-1,5-hexadiene with diethylamine." Collection of Czechoslovak Chemical Communications 50, no. 8 (1985): 1727–36. http://dx.doi.org/10.1135/cccc19851727.

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Reaction of diethylamine with 3-chlorononafluoro-1,5-hexadieae (I) in molar ratio of 1.5 : 1 to 2 : 1 at -30 to -17 °C gives N,N-diethyl-1,1,2,3,4,4,5,6,6-nonafluoro-2,5-hexadienylamine (II) which is easily hydrolyzed to N,N-diethyl-2,3,4,4,5,6,6-heptafluoro-2,5-hexadienamide (III). The same reaction with the molar ratio 4 : 1 at 0-6 °C and at 40 °C produces a mixture of N,N,N',N'-tetraethyl-1,1,2,3,4,5,6,6-octafluoro-2,4-hexadiene-1,6-diamine (IV), N,N,N',N'-tetraethyl-1,1,2,3,4,4,5,6,6-nonafluoro-2-hexene-1,6-diamine (V), and N,N,N',N'-tetraethyl-1,2,3,3,4,5,6,6-octafluoro-1,4-hexadiene-1,6-diamine (VI), which on hydrolysis gives N,N,N',N'-tetraethyl-2,3,4,5-tetrafluoro-2,4-hexadienediamide (VII) and N,N,N',N'-tetraethyl-2,3,4,4,5-pentafluoro-2-hexenediamide (VIII). Reaction of the mixture of diamines IV-VI with methanol or 1-propanol gives dimethyl or dipropyl 2,3,4,5-tetrafluoro-2,4-hexadienedioate (Xa,b), respectively. Stereospecificity of the chlorine substitution in perfluoroallyl grouping and the reaction mechanism are discussed. Conformation of the butadiene skeleton of these compounds is also discussed on the basis of calculation of 19F NMR spectra of trans,trans-2,3,4,5-tetrafluoro-2,4-hexadienedioic acid (IX) and its dimethyl ester Xa.

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23

Rivera, Augusto, Ingrid Miranda-Carvajal, and Jaime Ríos-Motta. "Cleaner and Efficient Green Chemistry Synthesis of N,N´-Dibenzyl or N,N´-(2-Hydroxybenzyl)-Ethane-1,2-Diamine,-Propane-1,3-Diamine and -1,3-Diamino-2-Propanol." International Journal of Chemistry 8, no. 4 (September 28, 2016): 62. http://dx.doi.org/10.5539/ijc.v8n4p62.

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An efficient and highly eco-friendly protocol for the preparation of N,N´-dibenzyl or N,N´-(2-hydroxybenzyl)diamines via the reduction of the corresponding di-Schiff bases that produces a good yield using water as a solvent without the need for catalysis or the azeotropic removal of water has been developed. These symmetric diimines have been reduced to their corresponding diamines with sodium borohydride using a catalyst- and solvent-free protocol with excellent yield. Mild conditions, high yields, and a simple work-up procedure are the primary benefits of this protocol.

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24

Dieck, Heindirk Tom, and Michael Zettlitzer. "Darstellung und ReaktionenN-silylierter En-diamine, II [2 + 2]-Cycloadditionen: Synthese von 1,4-Diamino-1,3-butadien-2,3-dicarbonsäure-Derivaten." Chemische Berichte 120, no. 5 (May 1987): 795–801. http://dx.doi.org/10.1002/cber.19871200518.

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25

Smith, J. G., and J. W. Connell. "Chemistry and Properties of Imide Oligomers from Phenylethynyl-Containing Diamines." High Performance Polymers 12, no. 1 (March 2000): 213–23. http://dx.doi.org/10.1088/0954-0083/12/1/318.

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As an extension of work on pendent phenylethynyl-containing imide oligomers, three new diamines containing pendent phenylethynyl groups were prepared and characterized. These diamines were used to prepare pendent and pendent and terminal phenylethynyl imide oligomers via the amide acid route in N-methyl-2-pyrrolidinone at a calculated number average molecular weight of 5000 g mol−1. The pendent phenylethynyl groups were randomly distributed along the oligomer backbone and provided a means of controlling the distance between reactive sites. The imide oligomers were characterized and thermally cured, and the cured polymers evaluated as thin films and compared with materials of similar composition prepared from 3,5-diamino-4′-phenylethynylbenzophenone. This work was performed as part of a continuing research effort to develop structural resins for potential aeronautical applications.

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26

Vyskočil, Štěpán, Martin Smrčina, and Pavel Kočovský. "A Facile Synthesis of the Enantiopure, Nitrogen-Substituted 2,2'-Diamino-1,1'-binaphthyls as Potential Ligands for Catalytic Asymmetric Reactions." Collection of Czechoslovak Chemical Communications 63, no. 4 (1998): 515–19. http://dx.doi.org/10.1135/cccc19980515.

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Reductive alkylation of (R)-(+)-2,2'-diamino-1,1'-binaphthyl (1) with various ketones has been accomplished by means of NaBH4/H2SO4 in THF at room temperature. Bisalkylation predominated with the sterically less demanding acetone (1→3a; 82%), whereas the bulky 2-adamantanone afforded mainly the monoalkylated product 4c (71%). Both mono- and bisalkylated diamines (R)-3 and (R)-4 were reductively permethylated on reaction with CH2O, NaBH4, and H2SO4. The Pd(0)-catalyzed phenylation of (R)-(+)-1 with PhBr afforded the N,N'-diphenyl derivative (R)-7 (70%).

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27

Angus, PM, BT Golding, SS Jurisson, AM Sargeson, and AC Willis. "Intramolecular Condensation Reactions of S-Methylmethionine Coordinated to Cobalt(III)." Australian Journal of Chemistry 47, no. 3 (1994): 501. http://dx.doi.org/10.1071/ch9940501.

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The sulfonium salt [(en)2CoO2CCH(NH2)(CH2)2S(CH3)2]3+ (en = ethane-1,2-diamine), prepared by methylation of the thioether group of N,O-coordinated methionine , undergoes a set of complex, intramolecular condensations, oxidations, and rearrangements in aqueous base to give a novel pentadentate cobalt(III) complex (c. 20%) of the 1,9-diamino-4-hydroxy-3,7-diazanonane-4-carboxylate ion ( dhnc ). Its structure has been determined by X-ray crystallographic analysis as trans(O,O)-[Co( dhnc )(OH2)](ClO4)2.2H2O. The crystals were monoclinic, space group P 21/c with a 9.053(2), b 29.437(7), c 7.661(1) Ǻ, β 106.63(1)°, and Z 4; 2383 data with I ≥ 3σ(I) were refined to conventional R factors of 0.046 and 0.060. Investigations concerning the mechanism for the formation of this complex are described.

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28

Clarke, Jeff D., Shasta L. Moser, and Keith Vaughan. "Synthesis and characterization of a series of 3-methyl-3-{3-[1-methyl-3-aryl-2-triazenyl]propyl}-1-aryl-1-triazenes and related compounds." Canadian Journal of Chemistry 84, no. 6 (June 1, 2006): 831–42. http://dx.doi.org/10.1139/v06-074.

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A series of diazonium salts has been coupled to both secondary nitrogen atoms of the bis-secondary amine, N,N′-dimethyl-1,3-propanediamine (MeNHCH2CH2CH2NHMe), to afford the new bistriazene series, the 3-methyl-3-{3-[1-methyl-3-aryl-2-triazenyl]propyl}-1-aryl-1-triazenes (9). These compounds have been fully characterized by IR and NMR spectroscopy, with supporting data from elemental analysis and high-resolution mass spectrometry. A limited number of model compounds in the N,N-dimethyl-N-{3-[1-methyl-3-aryl-2-triazenyl]propyl}amine series (10) have been synthesized to aid in the interpretation of the NMR spectra of the bistriazenes (9). A series of related compounds, the 3-ethyl-3-{(E)-4-[1-ethyl-3-aryl-2-triazenyl]-2-butenyl}-1-aryl-1-triazenes (11), have been synthesized by diazonium coupling with the bis-secondary amine N,N′-diethyl-2-butene-1,4-diamine (15), and the diazonium coupling reaction with trans-N,N′-dimethycyclohexane-1,2-diamine (19) has been used to prepare another related series of bistriazenes, the 3-methyl-3-{2-[1-methyl-3-aryl-2-triazenyl]cyclohexyl}-1-aryl-1-triazenes (12). The 1H NMR spectra of these compounds are complex because of the presence of two chiral centres in the cyclohexanediamine moiety; the diastereotopic protons of the methylene groups in the cyclohexane ring are clearly distinguished in the 500 MHz spectra of these compounds.Key words: triazene, bistriazene, synthesis, nuclear magnetic resonance, propanediamine, 1,4-diamino-2-butene, cyclohexanediamine.

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29

Harris, Frank W., Yoshimitsu Sakaguchi, Mitsuhiro Shibata, and Stephen Z. D. Cheng. "Organo-Soluble Polyimides: Synthesis and Characterization of Polyimides Containing Phenylated p-Biphenyl and p-Terphenyl Units." High Performance Polymers 9, no. 3 (September 1997): 251–61. http://dx.doi.org/10.1088/0954-0083/9/3/005.

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4, 4′-diamino-2, 2′-diphenylbiphenyl (1), 4,4″-diamino-2′, 3′, 5′-triphenyl- p-terphenyl (2a) and 4,4″-diamino-2′, 3′, 5′, 6′-tetraphenyl- p-terphenyl (2b) have been polymerized with several aromatic dianhydrides in refluxing m-cresol containing isoquinoline to afford a series of phenylated polyimides. The polymerization mixtures of 1 and 3, 3′, 4, 4′-biphenyltetracarboxylic dianhydride (BPDA) and 3, 3′4, 4′-benzophenonetetracarboxylic dianhydride (BTDA) and of 2a and pyromellitic dianhydride (PMDA) set to gel-like structures upon cooling. The gels, which displayed optical anisotropy typical of a liquid crystalline-like phase, could be dissolved by heating and re-formed by cooling. Although the p-catenated, rigid-rod polymers obtained from the diamines and PMDA were only soluble in concentrated sulphuric acid, the polymers that were prepared from 1 and 2a and 3, 3′, 4, 4′-diphenylethertetracarboxylic dianhydride (ODPA), 3, 3′, 4, 4′-diphenylsulphonetetracarboxylic dianhydride (DSDA) and 2, 2-bis[4-(1, 2-dicarboxyphenyl)]-1, 1, 1, 3, 3, 3-hexafluoropropane dianhydride (6FDA) were soluble in N-methyl-2-pyrrolidinone (NMP), m-cresol and chlorinated solvents. In general, polymers prepared from 2a were the most soluble, while polymers prepared from 2b were the least soluble. The intrinsic viscosities of the polymers ranged from ′.61 to 5.1 dl g−1 in concentrated sulphuric acid or NMP at 3′°C. The glass transition temperatures of most of the polymers could not be detected with differential scanning calorimetry. The temperatures at which the polymers underwent 5% weight losses when subjected to thermal gravimetric analysis ranged from 5″ to 6′°C in both air and nitrogen. Several of the polymers could be solution cast into thin, water-white flexible films.

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30

Golz, Christopher, Prisca Eckert, and Carsten Strohmann. "Anellierte Diamine als nützliche Dikationen am Beispiel der Darstellung von Halocupratsalzen / Anellated Diamines as valuable Dications using the Example of Halocuprate Salts." Zeitschrift für Naturforschung B 69, no. 11-12 (December 1, 2014): 1395–401. http://dx.doi.org/10.5560/znb.2014-4174.

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Abstract Diamines such as (R,R)-TMCDA (1) form anellated dications with dihalomethanes, which were obtained in the presence of copper(I)halides as salts containing halocuprate anions. Using the chiral diamine (R,R)-TMCDA (1) and its meso-form cis-TMCDA (2) trichloro- and tribromocuprates with trigonal-planar geometry, and with TMEDA (3) a continuous chain of copper(I)iodid were formed. The crystal structures were discussed and compared in terms of the influence of the dication on the structural behavior of the corresponding anion. Overall we revealed an easy access to chiral or achiral dications which are based on the readily available (R,R)-TMCDA (1) and its isomer cis-TMCDA (2).

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31

Akimoto, Satoshi, Mitsutoshi Jikei, and Masa-aki Kakimoto. "Preparation and Properties of Novel Aromatic Polyimides from 4,4′-Diamino-4″ -Hydroxytriphenylamine and Aromatic Tetracarboxylic Dianhydrides." High Performance Polymers 12, no. 1 (March 2000): 197–203. http://dx.doi.org/10.1088/0954-0083/12/1/316.

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Novel aromatic polyimides containing hydroxytriphenylamine units were prepared from 4,4′-diamino-4″-hydroxytriphenylamine 1 and various aromatic tetracarboxylic dianhydrides 2. The glass transition temperatures ( Tgs) of these polyimides were in the range of 274–388 °C and the 10% weight loss temperatures ( T d10s) were above 462 and 511 °C in air and nitrogen respectively. Polyimide 4f prepared from diamine 1 and 4,4′-hexafluoroisopropylidenebis(phthalic anhydride) (6FDA) was soluble not only in organic solvents such as N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N, N-dimethylformamide, 1, 3-dimethyl-2-imidazolidone and dimethyl sulfoxide but also in tetramethylammonium hydroxide aqueous solution. Other resulting polyimides were not soluble in organic solvents. The resulting polyimides 4 possessed Tgs about 20–70 °C higher and poorer solubilities than the previously reported polyimides prepared from 4,4′-diaminotriphenylamine and various aromatic tetracarboxylic dianhydrides. These results indicated that polymer properties such as thermal behaviour and solubilities were influenced by the intermolecular interaction of hydrogen bonding due to hydroxy units.

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32

Trilleras, Jorge, Jairo Quiroga, Justo Cobo, Antonio Marchal, Manuel Nogueras, John N. Low, and Christopher Glidewell. "Anhydrous versus hydrated N 4-substituted 1H-pyrazolo[3,4-d]pyrimidine-4,6-diamines: hydrogen bonding in two and three dimensions." Acta Crystallographica Section B Structural Science 64, no. 5 (September 15, 2008): 610–22. http://dx.doi.org/10.1107/s0108768108019903.

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Ten new N 4-substituted 1H-pyrazolo[3,4-d]pyrimidine-4,6-diamines have been synthesized and the structures of nine of them are reported here, falling into two clear groups, those which are stoichiometric hydrates and those which crystallize in solvent-free forms. In each of N 4-methyl-N 4-phenyl-1H-pyrazolo[3,4-d]pyrimidine-4,6-diamine, C12H12N6 (I), N 4-cyclohexyl-N 4-methyl-1H-pyrazolo[3,4-d]pyrimidine-4,6-diamine, C12H18N6 (II), and N 4-(3-chlorophenyl)-1H-pyrazolo[3,4-d]pyrimidine-4,6-diamine, C11H9ClN6 (III), the molecules are linked into hydrogen-bonded sheets. The molecules of 2-{4-(6-amino-1H-pyrazolo[3,4-d]pyrimidin-4-yl)piperazin-1-yl}ethanol, C11H17N7O (IV), are linked into a three-dimensional framework, while the structure of N 4-methyl-N 4-(4-methylphenyl)-1H-pyrazolo[3,4-d]pyrimidine-4,6-diamine monohydrate, C13H14N6·H2O (V), is only two-dimensional despite the presence of five independent hydrogen bonds. The stoichiometric hemihydrates N 4-ethyl-N 4-phenyl-1H-pyrazolo[3,4-d]pyrimidine-4,6-diamine hemihydrate, C13H14N6·0.5H2O (VI) and N 4-(4-methoxyphenyl)-N 4-methyl-1H-pyrazolo[3,4-d]pyrimidine-4,6-diamine hemihydrate, C13H14N6O·0.5H2O (VII), exhibit remarkably similar sheet structures, despite different space groups and Z′ values, Z′ = 0.5 in C2/c for (VI) and Z′ = 1 in P\bar 1 for (VII). N 4-4-Benzyl-N 4-phenyl-1H-pyrazolo[3,4-d]pyrimidine-4,6-diamine monohydrate, C18H16N6·H2O (VIII), crystallizes with Z′ = 2 in P21/n, and the four independent molecular components are linked into sheets by a total of 11 intermolecular hydrogen bonds. The sheet structure in {4-(pyrrolidin-1-yl)-1H-pyrazolo[3,4-d]pyrimidine-6-amine} ethanol hemisolvate hemihydrate, C9H12N6·0.5C2H6O·0.5H2O (IX), is built from the pyrimidine and water components only; it contains eight independent hydrogen bonds, and it very closely mimics the sheets in (VI) and (VII); the ethanol molecules are pendent from these sheets. The N 4-alkyl-N 4-aryl-4-aminopyrazolopyrimidine molecules in (I), (V)–(VIII) all adopt very similar conformations, dominated in each case by an intramolecular C—H...π(arene) hydrogen bond: this interaction is absent from (III) where the molecular conformation is entirely different and probably dominated by the intermolecular hydrogen bonds.

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33

Bosco, Bartolomeo, Andrea Defant, Andrea Messina, Tania Incitti, Denise Sighel, Angela Bozza, Yari Ciribilli, Alberto Inga, Simona Casarosa, and Ines Mancini. "Synthesis of 2,6-Diamino-Substituted Purine Derivatives and Evaluation of Cell Cycle Arrest in Breast and Colorectal Cancer Cells." Molecules 23, no. 8 (August 10, 2018): 1996. http://dx.doi.org/10.3390/molecules23081996.

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Reversine is a potent antitumor 2,6-diamino-substituted purine acting as an Aurora kinases inhibitor and interfering with cancer cell cycle progression. In this study we describe three reversine-related molecules, designed by docking calculation, that present structural modifications in the diamino units at positions 2 and 6. We investigated the conformations of the most stable prototropic tautomers of one of these molecules, the N6-cyclohexyl-N6-methyl-N2-phenyl-7H-purine-2,6-diamine (3), by Density Functional Theory (DFT) calculation in the gas phase, water and chloroform, the last solvent considered to give insights into the detection of broad signals in NMR analysis. In all cases the HN(9) tautomer resulted more stable than the HN(7) form, but the most stable conformations changed in different solvents. Molecules 1–3 were evaluated on MCF-7 breast and HCT116 colorectal cancer cell lines showing that, while being less cytotoxic than reversine, they still caused cell cycle arrest in G2/M phase and polyploidy. Unlike reversine, which produced a pronounced cell cycle arrest in G2/M phase in all the cell lines used, similar concentrations of 1–3 were effective only in cells where p53 was deleted or down-regulated. Therefore, our findings support a potential selective role of these structurally simplified, reversine-related molecules in p53-defective cancer cells.

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34

Hamciuc, Elena, Mihaela Homocianu, Corneliu Hamciuc, and Ionela-Daniela Carja. "Synthesis and photophysical study of new blue fluorescent poly(azomethine-1,3,4-oxadiazole)s containing dimethylamino groups." High Performance Polymers 30, no. 3 (March 9, 2017): 339–46. http://dx.doi.org/10.1177/0954008317697367.

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New aromatic polyazomethines were synthesized by polycondensation reaction of a diamine containing 1,3,4-oxadiazole ring, namely, 4,4′-diamino-4″-[2-(4-phenoxy)-5-(4-dimethylaminophenyl)-1,3,4-oxadiazole)]triphenylmethane, with terephthalic aldehyde or bis(4-formylphenoxyphenyl)fluorene, by using N-methyl-2-pyrrolidinone (NMP) as solvent. The polymers were easily soluble in polar solvents, such as NMP, N, N-dimethylacetamide, or chloroform, and showed high thermal stability with the initial decomposition temperature above 415°C and the temperature of 10% weight loss in the range of 450–460°C. They exhibited high char yield at 800°C in the range of 52–56%. Optical properties were studied by absorption and photoluminescence spectra. In solution, the polymers presented two absorption maxima in the ranges 273–278 and 330–346 nm and emitted violet-blue light in the range of 413–468 nm, depending on the solvent polarity. The Stokes shift and emission quantum yield values depend on the polymer structure and solvent polarity. The emission intensity in NMP solution was enhanced upon increasing the HCl concentration, while the absorption spectral profile was slightly influenced.

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35

Goel, Ravindra K., Satya P. Gupta, Sangeeta Sharma, and Chanchal Gupta. "Spectral investigations of 4,5-diamino-6-hydroxy-2-mercaptopyrimidine and 4,6-diamino-2-mercaptopyrimidine." Journal of the Chemical Society, Faraday Transactions 2 82, no. 2 (1986): 123. http://dx.doi.org/10.1039/f29868200123.

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36

Abram, Ulrich, Sonja Abram, Wolfgang Hiller, Gillian F. Morgan, John R. Thornback, Marcel Deblaton, and Joachim Stach. "Synthesis, Characterization and Crystal Structure of {N-(2-Mercaptoacetyl)-N′-[4-(pentene-3-one-2)]ethane-1,2-diaminato } oxotechnetium(V)." Zeitschrift für Naturforschung B 46, no. 4 (April 1, 1991): 453–58. http://dx.doi.org/10.1515/znb-1991-0406.

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{ N-(2-Mercaptoacetyl)-N′-[4-(pentene-3-one-2)]ethane-1,2-diaminato} oxotechnetium(V) has been prepared by the reaction of (Bu4N)TcOX4 complexes (X = Cl, Br) with N-(mercaptoacetyl)-N′-[4-(pentene-3-one-2)]ethane-1,2-diamine in methanolic solution. The compound forms dark red crystals which were characterized by elemental analysis, IR and 1H NMR spectroscopy, mass spectrometry, as well as an X-ray structure determination. The compound crystallizes triclinic in the centrosymmetric space group PĪ with a = 776.50(3), b = 819.69(6), c = 1040.43(7) pm, α = 92.944(6)°, β = 110.805(5)° and γ = 109.957(5)°. The final R value is 0.023. In the monomeric complex the five coordinate technetium atom exhibits a square pyramidal environment with the donors of the tetradentate ligand in the basal plane and the oxo ligand in the apical position. The bond length Tc–O = 165.7(2) is within the normal range of Tc=O double bonds.

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37

Vyskočil, Štěpán, Luděk Meca, Jiří Kubišta, Petr Maloň, and Pavel Kočovský. "Synthesis of C2-Symmetrical [1,1'-Binaphthalene]-2,2'-diamines with Additional Chelating Groups Attached to the Nitrogen Atoms as Potential Ligands for Asymmetric Catalysis." Collection of Czechoslovak Chemical Communications 65, no. 4 (2000): 539–48. http://dx.doi.org/10.1135/cccc20000539.

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Reductive amination of 2-hydroxybenzaldehyde, using a combination of NaBH4 and (R)-[1,1'-binaphthalene]-2,2'-diamine, served as the key step in the synthesis of the potentially tetradentate ligands (R)-N,N'-bis(2-hydroxybenzyl)[1,1'-binaphthalene]-2,2'-diamine and (R)-N,N'-bis(2-hydroxybenzyl)-N,N'-dimethyl[1,1'-binaphthalene]-2,2'-diamine. In analogy, amination of 2-bromobenzaldehyde with (R)-[1,1'-binaphthalene]-2,2'-diamine produced (R)-N,N'-bis(2-bromobenzyl)[1,1'-binaphthalene]-2,2'-diamine, whose conversion into the novel diphosphine ligand (R)-N,N'-bis[2-(diphenylphosphino)benzyl]-N,N'-dimethyl- [1,1'-binaphthalene]-2,2'-diamine was readily attained in two steps. CD spectra of the new binaphthyl derivatives are presented.

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38

Kofod, P., E. Larsen, J. Springborg, S. Larsen, TA Larsen, RJ Geue, and GH Searle. "Sulfur- and Carbon-Bonded Forms of the Cobalt(III) Complex With the Ligands 2-Aminoethyl 3-Aminopropyl Sulfide and 1,1,1-Tris(aminomethyl)ethane." Australian Journal of Chemistry 47, no. 1 (1994): 111. http://dx.doi.org/10.1071/ch9940111.

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The new sulfur-bonded compound [Co(tame)( aeaps )] Cl3.H2O has been synthesized by the reaction of aeaps with Co(tame)Cl3 [tame = 1,1,1-tris( aminomethyl )ethane, and aeaps = 2- aminoethyl 3-aminopropyl sulfide or 3-thiahexane-1,6-diamine]. The Co(tame)( aeaps )3+ ion equilibrates in basic solution with the corresponding carbon-bonded species: Co(tame)( aeaps )3++HO-↔ Co(tame)(C-aeaps )2++H2O A salt of the carbon-bonded species, [Co(tame)(C- aeaps )](S2O6), has been isolated and its structure solved by X-ray diffraction analysis ( C- aeaps = 1,6-diamino-3-thiahexan-4-ide). The crystals are orthorhombic, Pna21, with cell dimensions a 20.455(10), b 9.960(10), c 8.982(10) Ǻ at 122(2) K. Preliminary thermodynamic and kinetic data are similar to the recently reported values for the corresponding coordination ion Co( tacn )( aeaps )3+ ( tacn = 1,4,7-triazacyclononane). In basic solution the Co(tame)( aeaps )3+ species exchanges one of its methylene protons orders of magnitude faster than any other methylene protons and also much faster than it forms the alkyl complex as shown by 13C n.m.r. measurements.

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39

Hussein, Falah H., Ahmed F. Halbus, Hussein A. K. Hassan, and Wisam A. K. Hussein. "Photocatalytic Degradation of Bismarck Brown G Using Irradiated ZnO in Aqueous Solutions." E-Journal of Chemistry 7, no. 2 (2010): 540–44. http://dx.doi.org/10.1155/2010/719674.

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In this study, a homemade photoreactor equipped with 125w/542 high pressure mercury lamp as a source for near-UV radiation, was used for photocatalytic degradation of aqueous solutions of Bismarck brown G, (C18H20N8Cl2),4-[5-(2,4-Diamino-5-methylphenyl)diazenyl-2-methylphenyl] diazenyl -6-methylbenzol-1,3-diamin using zinc oxide. The disappearance of the original colored reactant concentrations with irradiation time was monitored spectrophotometrically by comparison with unexposed controls. It is noticed that the photocatalytic degradation process was high at the beginning and then decreased with time following pseudo first-order kinetics according to the Langmuir–Hinshelwood model. The effects of zinc oxide mass, dye concentration and temperature on photocatalytic decolorization efficiency (P.D.E.) were studied. P.D.E. reached 95.76% for Bismarck brown G after 50 minutes of irradiation at 293.15 K P.D.E. was found to increase with increasing temperature and the activation energy of photocatalytic degradation was calculated and found to be equal to 32±1 kJ mol-1.

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40

Jamil, Muhammad, Nargis Sultana, Rizwan Ashraf, Maryam Bashir, Muhammad Fayyaz ur Rehman, Fariha Kanwal, Humna Ellahi, Changrui Lu, Wei Xing Zhang, and Muhammad Ilyas Tariq. "Bis (Diamines) Cu and Zn Complexes of Flurbiprofen as Potential Cholinesterase Inhibitors: In Vitro Studies and Docking Simulations." Crystals 11, no. 2 (February 20, 2021): 208. http://dx.doi.org/10.3390/cryst11020208.

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Alzheimer’s disease (AD) causes dementia and continuous damage to brain cells. Cholinesterase inhibitors can alleviate the condition by increasing communication between the nerve cells and reducing the risk of dementia. In an effort to treat Alzheimer’s disease, we synthesized flurbiprofen-based diamines (1,2 diaminoethane and 1,3 diaminopropane) Zn(II), Cu(II) metal complexes and characterized them by single-crystal X-ray analysis, NMR, (FT)-IR, UV-Vis, magnetic susceptibility, elemental analysis and conductivities measurements. Synthesized diamine metal complexes appeared in ionic forms and have distorted octahedral geometry based on conductivity studies, magnetic susceptibility and electronic studies. Single crystal X-ray diffraction analysis confirmed (2b) Cu(H2O)2(L1)2(L2)2 complex formation. Moreover, we tested all synthesized metal complexes against the cholinesterase enzyme that showed higher inhibition potential. In general, copper metal complexes showed higher inhibitory activities than simple metal complexes with flurbiprofen. These synthesized metal complexes may derive more effective and safe inhibitors for cholinesterases.

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41

Sharma, Kripa, S. C. Joshi, and R. V. Singh. "Synthesis, Characterization and Antifertility Activity of New Unsymmetrical Macrocyclic Complexes of Tin(II)." Metal-Based Drugs 7, no. 5 (January 1, 2000): 237–43. http://dx.doi.org/10.1155/mbd.2000.237.

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A new series of unsymmetrical macrocyclic complexes of tin(ll) has been prepared by the template process using bis(3-oxo-2-butylidene)propane-1,3-diamine as precursor. This affords a method to synthesize these complexes with various ring sizes. The tetradentate macrocyclic precursor [N4mL] reacts with SnCl2 and different diamines in a 1:1:1 molar ratio in refluxing methanol to give complexes of the type [Sn(N4mL)Cl2]. The ring expansion has been achieved by varying the diamine between the two diacetyl amino nitrogen atoms. The macrocyclic precursor and its metal complexes have been characterized on the basis of elemental analysis, molar conductance, molecular weight determinations, IR, H1 NMR,C13 NMR, Sn119 NMR and electronic spectral studies. An octahedral geometry around the metal ion is suggested for these complexes. On the basis of molecular weights and conductivity measurements, their monomeric and non-electrolytic nature has been confirmed. The precursor and complexes have been screened in vitro against a number of pathogenic fungi and bacteria to assess their growth inhibiting potential. The testicular sperm density and testicular sperm morphology, sperm motility, density of cauda epididymal spermatozoa and fertility in mating trails and biochemicals parameters of reproductive organs have been examined and discussed.

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42

Romero, M. A., J. M. Salas, R. López, M. D. Gutiérrez, K. Panneerselvam, K. K. Chacko, K. Aoki, and H. Yamazaki. "Zn(II) and Hg(II) complexes of 4,6-diamino-2-thiopyrimidine and 4,6-diamino-2-methylthiopyrimidine. Crystal structure of 4,6-diamino-2-methylthiopyrimidinium hemitetrachlorozincate(II)." Inorganica Chimica Acta 172, no. 2 (June 1990): 253–58. http://dx.doi.org/10.1016/s0020-1693(00)80864-6.

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43

Khalili, Sedigheh, and Zahra Rafiee. "Synthesis and properties of highly organosoluble aromatic polyimides containing N-(4-(di(1H-indole-3-yl)methyl)phenyl) moieties." High Performance Polymers 32, no. 1 (May 27, 2019): 83–90. http://dx.doi.org/10.1177/0954008319853031.

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A new diamine monomer containing indole unit, 3,5-diamino- N-(4-(di(1H-indol-3-yl)methyl)phenyl)benzamide, was successfully synthesized and applied in the preparation of a series of polyimides (PIs) via a conventional two-step polymerization procedure with three aromatic tetracarboxylic dianhydrides. The prepared polymers showed excellent solubility in organic solvents such as N-methyl-2-pyrrolidinone (NMP), N, N-dimethylacetamide, and N, N-dimethylformamide. Flexible and strong films of PIs were obtained via casting from their solutions. The glass transition temperature of these polymers was in the range of 223–264°C. They were fairly stable up to a temperature around 300°C and lost 10% weight at 372°C in nitrogen atmosphere. All of the polymers revealed absorption maxima around 323 nm with a fluorescence emission maxima around 378–406 nm in NMP. The cyclic voltammetry of the PIs exhibited an oxidation wave with a peak at 1.07 V. The resulting polymer films had tensile strengths from 83 MPa to 107 MPa, elongates at break of 7–10%, and tensile moduli of 2.2–2.3 GPa.

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44

Alfieri, Maria Laura, Mariagrazia Iacomino, Alessandra Napolitano, and Marco d’Ischia. "Reaction-Based, Fluorescent Film Deposition from Dopamine and a Diamine-Tethered, Bis–Resorcinol Coupler." International Journal of Molecular Sciences 20, no. 18 (September 13, 2019): 4532. http://dx.doi.org/10.3390/ijms20184532.

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The reaction-based deposition on various surfaces of an all-organic fluorescent coating is reported here, involving autoxidation of 2 mM dopamine in carbonate buffer at pH 9.0, in the presence of a 1 mM diamine–resorcinol coupler (Bis–Res) prepared from 2,4-dihydroxybenzaldehyde and hexamethylenediamine (HMDA). Spectral analysis of the films coupled with an LC-MS investigation of the yellow fluorescent mixture was compatible with the formation and deposition of HMDA-linked methanobenzofuroazocinone fluorophores. Both the emission properties and hydrophobicity of the film were abated in a reversible manner following exposure to acid vapors. These results provide an entry to efficient and practical fluorescent coating methodologies based on in situ generation and the deposition of wet adhesive, as well as fluorescent materials combining a strongly emitting fluorophore with the film-forming properties of long chain diamines.

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45

Wang, Fang-Ming. "5,6-Diamino-1,3-benzodithiole-2-thione." Acta Crystallographica Section E Structure Reports Online 66, no. 12 (November 13, 2010): o3184. http://dx.doi.org/10.1107/s1600536810046532.

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46

Karaghiosoff, Konstantin, William S. Sheldrick, and Alfred Schmidpeter. "4,6-Diamino-1,3,5-triaza-2-phosphapentalene." Chemische Berichte 119, no. 11 (November 1986): 3213–26. http://dx.doi.org/10.1002/cber.19861191103.

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47

Curtis, NF, GJ Gainsford, A. Siriwardena, and DC Weatherburn. "Compounds of Nickel(II) With trans-6,13-Dinitro- and trans-6,13-diamino-6,13-dimethyl-1,4,8,11-tetraazacyclotetradecane, with Structural Studies of Five (trans-6,13-Diamino-6,13-dimethyl-1,4,8,11-tetraazacyclotetradecane)nickel(II) Compounds." Australian Journal of Chemistry 46, no. 6 (1993): 755. http://dx.doi.org/10.1071/ch9930755.

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Compounds of NiII with the macrocyclic ligand trans-6,13-dimethyl-6,13-dinitro-1,4,8,11-tetraazacyclotetradecane ( dino ), which is formed by condensation of bis (ethane-1,2-diamine)nickel(II) salts, nitroethane and formaldehyde, are described, together with homologues formed by substituting propane-1,2-diamine and/or 1-nitropropane. The nitro functions of [Ni( dino )]2+ were reduced by catalytic hydrogenation to form (trans-6,13-diamino-6,13-dimethyl-1,4,8,11-tetraazacyclotetradecane)nickel(II), [Ni( diam )]2+, isolated as approximately equal amounts of two isomeric forms; designated α (with the R,S,R,S configuration of the chiral nitrogen centres, overall configuration 1α,4α,6β,8α,11α,13α), and β (with the R,R,S,S, 1α,4β,6α,8β,11α,13β configuration). The α-isomer is metastable, and in solution isomerizes to the β-isomer, with rate constant of 5.0(5)×10-5 s-1 in 2 mol l.-1. NaCl solution at 50°C, the rate of this reaction increasing in both acid and base. Protonation constants (pK at 25°C in 0.1 mol l.-1 NaClO4) for diam are 11.2(1), 9.7(1), 6.2(1), 5.3(1), and for the isomeric nickel(II) cations are α 4.94(2), 2.4(5); and β 4.5(1), 4.0(1). Compounds of diam with the β-configuration were prepared with triplet ground state NiII with diam in hexadentate coordination (e.g. β-[Ni(diam-N4)] Cln ) and in tetradentate coordination with the neutral (e.g. trans-β-[Ni(diam-N4)(NCS)2]) or diprotonated ligand (e.g. trans-β-[Ni(diamH2-N4)(NCS)2](CNS)2). Compounds prepared with the α-configuration with triplet ground-state NiII had pentadentate diam with the neutral (e.g. trans-α-[Ni(diam-N5)(H2O)]Cl2) or monoprotonated ligand (e.g. trans-α-[Ni(diamH-N5) Cl ] (ClO4)2). Singlet ground-state NiII compounds with the square planar diprotonated ligand were prepared for both configurations. Structures are reported for β-[Ni(diam-N6)](ClO4)2(H2O), R 0.062 for 5708 reflections; β-[Ni(diam-N6)] [ZnCl4].1.5H2O, R 0.064 for 4332 reflections; β-[Ni(diam-N6)]Cl2.6H2O, R 0.044 for 2001 reflections; trans-β-[Ni(diam-N4)(NCS)2] R 0.056 for 1521 reflections; and trans-α-[Ni(diamH-N5) Cl ](ClO4)2(H2O), R 0.047 for 2667 reflections.

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48

De Guzman, Manuel Reyes, Micah Belle Marie Yap Ang, Shu-Hsien Huang, Qing-Yi Huang, Yu-Hsuan Chiao, and Kueir-Rarn Lee. "Optimal Performance of Thin-Film Composite Nanofiltration-Like Forward Osmosis Membranes Set Off by Changing the Chemical Structure of Diamine Reacted with Trimesoyl Chloride through Interfacial Polymerization." Polymers 13, no. 4 (February 12, 2021): 544. http://dx.doi.org/10.3390/polym13040544.

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Thin-film composite (TFC) polyamide membranes formed through interfacial polymerization can function more efficiently by tuning the chemical structure of participating monomers. Accordingly, three kinds of diamine monomers were considered to take part in interfacial polymerization. Each diamine was reacted with trimesoyl chloride (TMC) to manufacture TFC polyamide nanofiltration (NF)-like forward osmosis (FO) membranes. The diamines differed in chemical structure; the functional group present between the terminal amines was classified as follows: aliphatic group of 1,3-diaminopropane (DAPE); cyclohexane in 1,3-cyclohexanediamine (CHDA); and aromatic or benzene ring in m-phenylenediamine (MPD). For FO tests, deionized water and 1 M aqueous sodium sulfate solution were used as feed and draw solution, respectively. Interfacial polymerization conditions were also varied: concentrations of water and oil phases, time of contact between the water-phase solution and the membrane substrate, and polymerization reaction time. The resultant membranes were characterized using attenuated total reflectance-Fourier transform infrared spectroscopy, field emission scanning electron microscopy, atomic force microscopy, and surface contact angle measurement to identify the chemical structure, morphology, roughness, and hydrophilicity of the polyamide layer, respectively. The results of FO experiments revealed that among the three diamine monomers, CHDA turned out to be the most effective, as it led to the production of TFC NF-like FO membrane with optimal performance. Then, the following optimum conditions were established for the CHDA-based membrane: contact between 2.5 wt.% aqueous CHDA solution and polysulfone (PSf) substrate for 2 min, and polymerization reaction between 1 wt.% TMC solution and 2.5 wt.% CHDA solution for 30 s. The composite CHDA-TMC/PSf membrane delivered a water flux (Jw) of 18.24 ± 1.33 LMH and a reverse salt flux (Js) of 5.75 ± 1.12 gMH; therefore, Js/Jw was evaluated to be 0.32 ± 0.07 (g/L).

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Reglinski, John, Michelle K. Taylor, and Alan R. Kennedy. "N,N′-Bis(2-methoxybenzylidene) adducts of ethane-1,2-diamine, propane-1,3-diamine and butane-1,4-diamine." Acta Crystallographica Section C Crystal Structure Communications 60, no. 3 (February 10, 2004): o169—o172. http://dx.doi.org/10.1107/s0108270104001404.

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50

Mirocki, Artur, and Artur Sikorski. "The Influence of Solvent on the Crystal Packing of Ethacridinium Phthalate Solvates." Materials 13, no. 22 (November 10, 2020): 5073. http://dx.doi.org/10.3390/ma13225073.

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The synthesis, structural characterization and influence of solvents on the crystal packing of solvated complexes of ethacridine with phthalic acid: 6,9-diamino-2-ethoxyacridinium phthalate methanol solvate (1), 6,9-diamino-2-ethoxyacridinium phthalate ethanol solvate (2), 6,9-diamino-2-ethoxyacridinium phthalate isobutanol solvate (3), and 6,9-diamino-2-ethoxyacridinium phthalate tert-butanol solvate monohydrate (4) are described in this article. Single-crystal XRD measurements revealed that the compounds 1–4 crystallized in the triclinic P-1 space group, and the 6,9-diamino-2-ethoxyacridinium cations, phthalic acid anions and solvent molecules interact via strong N–H···O, O–H···O, C–H···O hydrogen bonds, and C–H···π and π–π interactions to form different types of basic structural motifs, such as: heterotetramer bis[···cation···anion···] in compound 1 and 2, heterohexamer bis[···cation···alcohol···anion···] in compound 3, and heterohexamer bis[···cation···water···anion···] in compound 4. Presence of solvents molecule(s) in the crystals causes different supramolecular synthons to be obtained and thus has an influence on the crystal packing of the compounds analyzed.

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Journal articles on the topic '2-diamina'

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