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1
Cornet, Stephanie Michele Marie. "Synthesis and characterisation of some main-group compounds with bulky electron-withdrawing substituents." Thesis, Durham University, 2002. http://etheses.dur.ac.uk/4173/.
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Several new group 13, 14 and 15 derivatives with the ligands 2,4,6-(CF(_3))(_3)C(_6)H(_2) (Ar), 2,6- (CF(_3))(_2)C(_6)H(_3) (Ar') and / or 2,4-(CF(_3))(_2)C(_6)H(_3) (Ar") have been prepared. They have been characterised by multinuclear NMR spectroscopy and, for all isolated compounds, by elemental analysis and, where possible, single crystal X-ray diffraction. Reaction of ArLi or the mixture Ar'Li/Ar"Li with BCI3 has led to the characterisation of several mono- and disubstituted compounds, but attempted substitution in AICI3 was unsuccessful. Reaction of EC1(_4) (E = Si, Ge, Sn) with the Ar'Li/Ar"Li mixture yielded predominantly the less sterically hindered disubstituted product Ar"(_2)ECl(_2) for E = Si and Ge but to Ar'(_2)ECl(_2) for E = Sn. In the case of B or Si, chlorine exchange is observed and Ar(_2)BF, Ar(_2)SiF(_2) and Ar'(_2)SiF(_2) have been synthesised. Ar(_2)SiF(_2) is the only product identified in the reaction of ArLi with SiC1(_4). Reaction of ArLi or the Ar'Li/Ar"Li mixture, in an appropriate ratio, with group 15 derivatives gave rise to several mono-or disubstituted compounds of the type ArEX(_2), Ar(_2)EX, Ar'EX(_2), Ar"EX(_2), Ar"(_2)EX and Ar'Ar"EX (E = P or As; X = H, CI or Br). (^19)F NMR spectra of Ar'Ar"EX show that, for the two ortho-CF(_3) groups of the Ar' moiety, there is free rotation of the aryl group around the central atom. A series of variable temperature studies has been carried out, and allowed the determination of the rotational energy barrier of the molecule. For the first time, the molecular structures of derivatives containing three fluoroxyl ligands have been determined (Ar"(_3)B and Ar'Ar"(_2)Sb).The synthesis of some new platinum complexes has been facilitated by reaction of phosphanes with the platinum dimer [(PtCl(_2)(Pet(_3))](_2) or [(PtBr(_2)(Pet(_3))](_2). Reactions of the platinum dimer with arsane derivatives have not been successful. Halogen exchange was observed between bromophosphane ligands and CI groups on the platinum. Attempts have been made to synthesise new P=E derivatives containing the electron- withdrawing substituents Ar or Ar' via reaction with the chlorine abstractor W(PMe(_3))(_6)- ArP=PAr and Ar'P=PAr' have been prepared. Synthesis of the first phosphaalkyne containing Ar or Ar' has been attempted by reacting a phosphaalkene with a Pt(0) species.
2
Sequeira, L. J. "Studies on main group and transition metal compounds containing a sterically demanding, electron-withdrawing ligand." Thesis, Durham University, 1996. http://etheses.dur.ac.uk/5396/.
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The studies described herein relate to the co-ordination chemistry of l,3,5-tris(trifluoromethyl)benzene, Ar(^F)H. The unique combination of steric bulk and a highly electron-withdrawing nature found in the a- bound Ar(^F) ligand has already been exploited to stabilise a variety of unusual main group compounds including the surprisingly air- and moisture-stable diphosphene Ar(^F)P=Par(^F). Other examples are discussed in the introductory chapter, as is the increasingly active area of diphosphene research. Chapter 2 describes the synthesis and structural characterisation of six early σ-Ar(^F) transition metal complexes, Mo(N(^t)Bu)(_2)(Ar(^F))2, Cr(NAd)(_2)(Ar(^F))(_2), [Mo(NAr)(_2)(Ar(^F))Cl-LiCl(dme)](_2), V(Ar(^F))(_2)Cl(thf), V(Ar(^F))(_3)-O -Li(thf)(_3) and Cr(Ar(^F))(_2)(PMe(_3))(_2). The first five of these compounds exhibit the rare phenomenon of weak metal-fluorine interactions, which is discussed in terms of several structural factors such as tilting of the aryl ring towards the direction of the M-F interaction The co-ordination chemistry of the diphosphenes Ar(^F)p=PArF, Ar*P=PAr* and Ar*P=PArF (Ar* = 2,4,6-(^t)BuC6H3) is reported in chapter 3. Ar(^F)p=Par(^F) is shown to displace olefins from a bis(imido)molybdenum centre to generate complexes such as Mo(NR)(_2)(PMe)(_3)(Ti2-ArFp=PArF) (R = tBu, 2,6-iPr2C6H3). The crystal structure of Mo(NtBu)2(PMe)3(Ti2- ArFp=PArF) has been elucidated. Related investigations have focused on the co-ordination mode of the diphosphenes Ar*P=PAr* and Ar*P=PArFwith [Pt(PEt3)Cl2]2/ and a variety of Til-complexes has been spectroscopically observed. The development of phosphorus based analogue of the industrially important olefin metathesis reaction is detailed in chapter 4. The reaction of ArPCl2, [Ar = Ar(^F), Ar* and 2,6-(CF3)2-C6H3 (Ar(^f1)] with the halide abstractor W(PMe3)6 leads to the generation of ArP=PAr via a postulated [W]=PAr phosphinidene intermediate. The unsymmetrical diphosphene ArFp=PAr* has been synthesised analogously from a mixture of ArFPCl2 and Ar*PCl2 with W(PMe3)6- When Ar is small (2,4,6-iPr3C6H2, 2,4,6- Me3C6H2), ArPCl2 reacts with W(PMe3)6 to give three-membered tricyclophosphanes, [ArP](_3) π-bound complexes of the Ar(^F)H ligand have been synthesised via metal vapour synthesis experiments, carried out in collaboration with Prof. F.G.N. Cloke at Sussex University. Chapter 5 describes the preparation of the bis-arene complexes M(T|6-ArFH)2 (M=Cr, V, Nb) and Ru(Ti6-ArFH)(Ti4-ArFH).Full experimental details and characterising data for chapters 2-5 are collected in chapter 6.
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Rabinowitz, Daniel Joshua. "Electrochemical Studies of Substituted Anthraquinones." Digital Archive @ GSU, 2008. http://digitalarchive.gsu.edu/chemistry_theses/15.
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Electrochemical potentials of a series of anthraquinone derivatives were studied in both aqueous solution and acetonitrile. The long term goal of this work was to find derivatives which could be reduced easily for studies of photoinduced electron transfer in DNA. Our immediate goal was to find the substitution group that gave the least negative redox potential value. Of all derivatives studied, the anthraquinone imides as a class had the least negative redox potentials, in the range of -0.600 to -0.550 V vs. SCE. One of the anthraquinones studied, one derivative (deoxyadenosine conjugated with an ethynyl linker to an anthraquinone with two ester substituents) was also in this range. A study of a series of anthraquinones conjugated with ethynyl and ethanyl linkers showed that the ethynyl linker was more effective than the ethanyl linker in lowering the redox potential of anthraquinone.
4
Ahmed, K. M. "Diels-Alder reaction of quinones carrying electron-withdrawing groups." Thesis, University of Manchester, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.234154.
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Lou, chia-hao, and 樓家豪. "The study of phenyl azides reaction with electron-withdrawing group alkenes." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/92384838214977891532.
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碩士中原大學
化學研究所
99
This study is the use of phenyl azide (for example: benzyl azide, chlorophenyl azide) with the electron-withdrawing alkenes (for example: methyl methacrylate, acrylonitrile) reaction. To investigate the reaction under high temperature condition between the previous results at room temperature and under high pressure at room temperature compared the results of what these differences. The experiment features a fast and simple preparation aziridine, let aniline turn into azidobenzene,and then reaction with the electron-withdrawing alkenes under 100 degree. The products are aziridine and triazole . the triazole turn into aziridine as faster as temperature increase. most patients do not need to experiment in the use of solvents as long as under high temperature conditions can be completed.
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CHANG, HSIEH MING, and 謝明璋. "Mechanistic Studies on The Thermal [m+n] Cycloadditions of Electron-Withdrawing Group Heptafulvenes and Electron-Donating Group Fulvenes." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/66903829394433213991.
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碩士中國文化大學
應用化學研究所
88
In order to determine the product selectivity，such as the diastereoselectivity，periselectivity，and regioselectivity，which is governed by steric effects and electronic effects of the exocyclic substituents on the fulvenes and heptafulvenes，the intermolcular cycloadditions of electron-rich disubstituted 2- (2，4-cyclopentien-1-ylidene)-1，3-dithiolanefulvene (3c)，with 8，8-dicyanoheptafulvene (9a) are investigated. The reaction of strong electron-deficient substituted heptafulvene 9a (LUMO) with the fulvene 3c (HOMO) afford [4+2] adducts 20a (syn) and 20b (anti) in a ratio of about 1.58：1 in 65％ yield.
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CHIU, JEN-CHUN, and 邱仁軍. "Synthesis and Characterization of Novel ConjugatedPoly(p-biphenylenevinylene) Containing Electron-withdrawing Trifluoromethyl Group." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/87088283578835160436.
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碩士國立臺灣科技大學
高分子系
98
The objective of this study is to introduce twisted biphenyl structure containing trifluoromethyl groups at 2 and 2’ positions into the main chain of the π-conjugated polymer. The incorporation twisted biphenyl structure has been proven to enhance the solubility of entire aromatic rod-like polymer effectively.This is a new method to improve the poor solubility of π-conjugated polymers. The novel π-conjugated polymers(CF3-PBPV) in this study were synthesized by using three new compounds, 2,2'-Bis(trifluoromethyl)-4,4'-biphenyldicarbaldehyde(6) 、2,2'-Bis(trifluoromethyl)-4,4'-bis(bromomethyl)biphenyl(8) and 2,2'-Bis(trifluoromethyl)-4,4'-bis(diethyl methylenephosphonate)biphenyl(9),through Gilch and Horner-Emmons reactions.We change monomer's molar ratio in Horner-Emmons reactions and add TEMPO in Gilch reaction to obtain different molecular weight PH-1,PH-2,PH-3 and PG-1,PG-2,respectively. The formed polymers have relatively high molecular weights in the range of 15000 to 149000 g/mole.These polymer's solubility is related to its molecular weight, when the molecular weight is smaller than 30000 g/mole under the room temperature could be dissolved in the common organic solvent (DMF, DMAc, NMP).PH-1 and PG-1 shows the glass transition at 231 and 234 ℃(by DSC),and the 5% decomposition temperature at 417 and 405 ℃,respectively.From UV-visible spectrometric analysis,PH-1 and PG-1 shows the maximum absorptions wavelength(λmax) at 341 and 321 nm.From photoluminesce spectrum,the formed polymer shows maximum emission at wavelength 395 nm.Wide angle X-ray diffraction exhibits PH-1 and PG-1 are amorphous.The energy gap (Eg) is 2.90 eV,calculated by cyclic voltammetry.These polymers exhibit high electronegativity(-3.04 eV)and high ionization potential(-5.94 eV).Because CF3-PBPV has the high glass transition temperature and the amorphous characteristic, therefore it could be applicable for organic luminescent material.
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Shen, Huang Jang, and 沈弘章. "One Pot Multiple-Steps Reaction of Allyl Azide and Alkenes Carrying Electron-Withdrawing Group." Thesis, 1993. http://ndltd.ncl.edu.tw/handle/24829901429854017836.
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碩士中原大學
化學學系
81
1,3-偶極環化加成反應是合成五元環最簡便而常見的方法之一, 近年已有 愈來愈多的化學家更深入地研究此類的反應, 經由選擇不同的偶極化合物 與雙鍵反應可得到不同的五元環雜環化合物。由疊氮化合物與雙鍵進行反 應,可獲得.DELTA.^2-1,2,3-三氮-五環化合物(.DELTA.^2-1,2,3- Triazoline)。依據G.L'abbe(1971)及 R.Huisgen(1966)的研究報告可知, 當1,2,3-三氮-五環化合物在其位置4上若有拉電子基(如酯基,醯基,氰基) 存在時,則三氮-五環化合物會進行可逆的異構化反應得到重氮乙酸酯(拉 電子基為酯基)。而重氮基亦是一個1,3-偶極官能基,可與雙鍵再進行偶極 環化反應,當重氮乙酸酯與另一分子烯類進行分子間偶極環化加成,得 到2-.blksq.唑類化合物(L'abbe與Huisgen的反應結果)。但若重氮乙酸酯 分子本身帶有雙鍵,則此雙鍵與重氮基進行分子內偶極環化加成反應,可獲 得一個二圓環化合物。在本研究中,以丙烯基疊氮與具拉電子基之烯類,如 丙烯酸甲酯,丙烯.blksq.,丙烯酸醯胺,乙烯基甲基酮或乙烯基乙基酮等反 應,都得到了相似的2,3,7-三氮-二環[3.3.0]類化合物。由丙烯基疊氮與 烯類的反應至產物之獲得 ,其間進行了分子間環化加成,分子內環化加成, 異構化及麥可加成等反應 ;同時反應中共破壞了五個鍵結及形成五個新鍵 結,並高產率地獲得 [3.3.0]-二圓環的新化合物o同時本文亦討論到溫度, 溶劑及反應濃度對反應結果的影響o
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Wei, Jun-Yu, and 魏俊育. "Synthesis, Structural Characterization and Magnetic Properties of Mononuclear and Polynuclear Lanthanide Complexes by Using Schiff-Base Ligands with Different Electron-Donation Group and Electron-Withdrawing Group." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/4pu6dq.
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碩士國立中興大學
化學系所
106
In this research, five kinds of Schiff-Base ligands are ultilized to synthesize sixteen complexes. Three polynuclear complexes are synthesized by ligand H3bsc. Complex(2) and complex(3) are novel octanuclear structure. Then, two Schiff-Base ligands with Different Electron-Donation Group (H-hmni) and Electron-Withdrawing Group (H-hdnb) generate nine mononuclear complexes. From complex(4) to complex(12) are mononuclear complexes. Complex(4)and complex(8) are isostructural complexes as well as complex(6) and complex(10). Finally, H-hmnoi and (H3dnoc) are ultilized to synthesize mononuclear and trinuclear complexes, respectively. Complex(14), (15), (16) have Single-Molecule Magnet behavior.
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Chen, Zhi Yu, and 陳志毓. "A further study on one pot multiple-steps reaction of allys azide and alkenes carrying electron-withdrawing group." Thesis, 1994. http://ndltd.ncl.edu.tw/handle/30670793132605119773.
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Ming-LunYang and 楊明崙. "Synthesis and characterization of new low bandgap copolymers containing electron withdrawing group as a side chain for bulk heterojunction solar cells." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/65836227263980447936.
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碩士國立成功大學
材料科學及工程學系碩博士班
98
We have successfully synthesized two new low bandgap copolymers. One is the alternating polyfluorene copolymer (PF-NAP?) based on dioctylfluorene and a donor-acceptor monomer with an electron-withdrawing moiety as a side chain via the Suzuki polymerization reaction. The other one is the random polycarbazole copolymer (PC-NAP) based on Br2-Carb-Benzene and a donor-acceptor monomer with an electron- withdrawing moiety as a side chain via the Yamamoto polymerization reaction. Both copolymers have excellent thermal stability. The 5% weight loss temperature (T5d) of the PF-NAP and PC-NAP are 431 and 460 °C, respectively. The resulting copolymers have low optical and electrochemical bandgaps. The optical bandgap and the electrochemical bandgap of PF-NAP are 1.79 and 1.90 eV, respectively. The optical bandgap and the electrochemical bandgap of PC-NAP are 1.75 and 1.88 eV, respectively. The bulk heterojuction polymer solar cells were fabricated with the conjugated polymers as the electron donor and 6,6-phenyl C61-butyric acid methyl ester (PCBM) as the electron acceptor. The power conversion efficiencies (PCE) of the solar cells based on copolymers PF-NAP : PCBM (1:5) and PC-NAP : PCBM (1:5) are 0.231% and 1.005%, respectively, under the illumination of AM 1.5 G, 100 mW/cm2.
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Cheng, Hong-Yi, and 陳鴻儀. "The synthesis of porphyrins with electron-withdrawing and -donating groups." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/64541561928294591379.
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碩士國立中興大學
化學系所
96
Abstract A series of zinc porphyrins with both electron donor and acceptor groups were synthesized for use as NLO chromophores in optoelectronic materials and devices.The porphyrin bridge connecting D and A groups should provide a pathway for strong electronic coupling between D and A. Organic molecules with strong electron donor and electron aceptor groups that are connected by a large conjugated π– electron system usually show high β values, so we utilized a ethynyl unit to extendπ– conjugation of the systems. The preparation of porphyrins with ethyne-linked functional groups can be achieved by the sonogashira cross-coupling method. Light - harvesting arrays that consist of porphyrin and perylene units were synthesized. These arrays show broad absorption in the visible region. The energy transfer between porphyrin and perylene pigments was investigated by fluorescence spectroscopy. We except that porphyrin – perylene systems have high energy conversion efficiency in solar cells.
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Shukla, Piyush Cowley Alan H. "New approaches to nitrogen ligands bearing electron withdrawing groups and their role in coordination chemistry." 2003. http://wwwlib.umi.com/cr/utexas/fullcit?p3116189.
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Shukla, Piyush 1977. "New approaches to nitrogen ligands bearing electron withdrawing groups and their role in coordination chemistry." 2003. http://hdl.handle.net/2152/12635.
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Chun-ChiaHsu and 許峻嘉. "Synthesis, Photophysics and Computation of 2-(2’-hydroxyl- 5’-methylphenyl)benzotriazole (TIN P) Derivatives with the Electron-Withdrawing Groups at C-11 Position." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/32824370336758106167.
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碩士國立成功大學
化學系碩博士班
100
In the present work, UV absorber, 2-(2’-hydroxyl-5’-methylphenyl) benzotriazole (1), has been taken as the starting material to synthesize various derivatives such as 2-(2’-hydroxyl-5’-methyl-3’-nitrophenyl) benzotriazole (2), 2-(2’-hydroxyl-5’-methyl-3’-sulfonphenyl)benzotriazole (3), 2-(2’-hydroxyl-3’- methoxymethyl-5’-methylphenyl)benzotriazole (4), 2-(2’-hydroxyl- 3’-butoxy- methyl-5’-methylphenyl)benzotriazole (5) and 2-(2’-methoxy- 5’-methylphenyl) benzotriazole (6). Each of the derivatives was dissolved in hexane, cyclohexane, methanol and DMSO, respectively, to measure the photophysical properties (UV/Vis and Fluorescence). Spectroscopic study of UV/Vis absorption and fluorescence emission in solution state, and theoretical study with density functional theory (DFT) method were employed to characterize these UV absorbers. According to the results of UV absorption and fluorescence emission, it was found compounds with electron- withdrawing groups in the C-11 site could promote the strength of intramolecular hydrogen bonding and compounds (4,5) were capable of preventing from interacting with the solvent, which was due to the steric effect from bulkyl substituent in the C-11 site. By using molecular orbital analysis, it was found we can reasonably analyze that compounds(1)-(5) prefer intramolecular proton transfer in excited state (1) to (5) as to deactivate the excited state.