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Journal articles on the topic '5-Dienes'

Author: Grafiati

Published: 4 June 2021

Last updated: 1 February 2022

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1

Bończa-Tomaszewski, Zbigniew. "The potassium permanganate oxidation of steroidal homoannular dienes." Canadian Journal of Chemistry 65, no. 3 (1987): 656–60. http://dx.doi.org/10.1139/v87-112.

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The oxidation of 3β-acetoxycholesta-5,7-diene (1) with potassium permanganate–sodium periodate reagent gave epoxy-diol 2 with almost quantitative yield. Similar oxidation of cholesta-2,4-diene (3) afforded, as well as epoxy-diols 5 and 6, products of cleavage of the double bonds. These results show that formation of epoxy-diols predominates in the case of hindered steroidal dienes (e.g., diene 1), whereas oxidation of unhindered steroidal dienes (e.g., diene 2) gives, in addition to epoxy-diols, products of cleavage of the double bonds.

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2

Butler, MS, and RJ Capon. "Norterpene Dienes From an Australian Marine Sponge Latrunculia brevis." Australian Journal of Chemistry 44, no. 1 (1991): 77. http://dx.doi.org/10.1071/ch9910077.

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The norditerpene diene acid (4) and norsesterterpene diene acid (5), along with their corresponding methyl esters (6) and (7), were isolated from an Australian marine sponge, Latrunculia brevis, and their structures determined by detailed spectroscopic analysis, chemical derivatization and degradation. Comment is made on the possible intermediacy of dienes such as (4)-(7) in the biosynthesis of norterpene cyclic peroxides, common to other Latrunculia species from the same locality.

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3

Piers, Edward, Richard W. Friesen, and Steven J. Rettig. "Annulation sequences employing methyl (E)- and (Z)-6-iodo-3-trimethylstannyl-2-hexenoates and related bifunctional reagents. Preparation of cisoidcis and cisoidtrans bicyclic dienes." Canadian Journal of Chemistry 70, no. 5 (1992): 1385–96. http://dx.doi.org/10.1139/v92-177.

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A useful annulation method leading to the stereospecific synthesis of structurally novel, functionalized bicyclic dienes is described. Alkylation of 2-(methoxycarbonyl)cyclopentanone (34) and 2-(methoxycarbonyl)cyclohexanone (35) with methyl (E)- and (Z)-6-iodo-3-trimethylstannyl-2-hexenoates (27, 28) provided the keto diesters 36–39. Conversion of these substances into the corresponding enol triflates 47–50, followed by palladium(0)-catalyzed ring closure of the latter compounds, afforded the bicyclic dienes 55–58. In similar fashion, the keto esters 34 or 35 were transformed into the dienes

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4

Maas, Gerhard, and Rainer Rahm. "A Proton-Catalyzed Dimerization of a 2-Amino-1,3-diene which Ultimately Yields a 3-Aminobicyclo[4.2.0]octa-2,4-diene." Zeitschrift für Naturforschung B 60, no. 6 (2005): 673–76. http://dx.doi.org/10.1515/znb-2005-0611.

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The 2-pyrrolidino-1,3-dienes (E)-5 and (Z)-5 are obtained by the reaction of lithium di(tertbutyl) cuprate with propyne iminium salt 3. Quantitative Z→E isomerization of 5 takes place within 4 hours at 20 °C. In benzene solution, (E)-5 slowly equilibrates with a [1,5]-H shift to form the 1-amino-1,3-diene derivative 6. In concentrated chloroform solution, however, (E)-5 is transformed into the 3-pyrrolidino-bicyclo[4.2.0]octa-2,4-diene 7 which is identified by X-ray crystal structure analysis. A mechanism for this transformation is proposed.

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5

Wang, Lizhong, Ting Wang, Chenlu Dai, Yang Li, and Cunde Wang. "Nickel-Catalysed Synthesis of 17-Arylandrosta-5,16-Dienes." Journal of Chemical Research 41, no. 11 (2017): 653–56. http://dx.doi.org/10.3184/174751917x15094552081206.

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An efficient Ni-catalysed coupling reaction between arylboronic acids and 17-trifluoromethanesulfonyl- 3β-acetoxyandrosta-5,16-diene which was obtained by the sulfonylation of 3β-acetoxylandrost-5-ene-17-one was developed to afford 17-aryl- 3β-acetoxy-androsta-5,16-dienes in moderate to good yields (52–85%). The structure of the 3,4-dimethoxyaryl product was confirmed by X-ray crystallography.

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6

Kreiter, Cornelius G., Kurt Nist та Joachim Kögler. "Gehinderte Ligandbewegungen in Übergangsmetallkomplexen, XXXI [1]. Synthese und Dynamik von Acetyl-carbonyl-η5-cyclopentadienyl-η4-dien-wolfram-Komplexen / Hindered Ligand Movements in Transition Metal Complexes, XXXI [1]. Syntheses and Dynamics of Acetyl-carbonyl-η5-cyclopentadienyl-η4-diene-tungsten Complexes". Zeitschrift für Naturforschung B 41, № 5 (1986): 599–605. http://dx.doi.org/10.1515/znb-1986-0512.

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Tricarbonyl-η5-cyclopentadienyl-methyl-tungsten (1) reacts upon UV irradiation with conjugated dienes, like 1,3-butadiene (2), E-1,3-pentadiene (3), 2-methyl-1,3-butadiene (4), 2,3-dimethyl-1,3- butadiene (5), 1,3-cyclopentadiene (6) and 1,3-cyclohexadiene (7), to give the corresponding, quasisquare- pyramidal [(η5-C5H5)W(CO)(COCH3)(η4-diene)] complexes (8-13). With the unsymmetrically substituted dienes 3 and 4, only one of the possible diastereotopic complexes are obtained. At 200 to 230 K, 8-12 show two isomers, which are distinguished by the orientations (o or u) of the diene with respect

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7

Liu, Hsing-Jang, Teng Ko Ngooi, and Eric N. C. Browne. "Diels–Alder reactions of 2-carbomethoxy-2-cyclohexen-1-one." Canadian Journal of Chemistry 66, no. 12 (1988): 3143–52. http://dx.doi.org/10.1139/v88-485.

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Under stannic chloride catalysis, 2-carbomethoxy-2-cyclohexen-1-one (5) was found to undergo Diels–Alder reaction with a variety of dienes to give directly the cis-1-octalone system possessing a functionalized substituent at the angular position. With unsymmetrically substituted dienes, the adducts were those predicted on the basis of the normal rules (ortho and para) governing the orientation of Diels–Alder addition. In cases where differing secondary orbital overlap would affect the stereochemistry of the adducts, the major isomer in each case was that produced by secondary overlap of the di

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8

Paquet, Jacques, and Paul Brassard. "Reactions of polar dienes with o-quinones." Canadian Journal of Chemistry 67, no. 8 (1989): 1354–58. http://dx.doi.org/10.1139/v89-207.

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The behaviour of various types of polar dienes towards halogenated ortho quinones has been investigated in a number of representative cases. As compared to the commonly used para analogues, o-quinones provide a wide range of products that indicate a keener response to the nature, number, and position of substituents on both reactants. 3-Halogenated-o-naphthoquinones 1 and 2 react smoothly with a representative vinologous ketene acetal 3, vinylketene acetals 4 and 5, and a monooxygenated diene 6 to provide variously substituted phenanthrenequinones 7–11. Only monooxygenated dienes on the other

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9

Mazerolles, Pierre, and Fabienne Gregoire. "5-germaspiro[4.4]nona-2,7-dienes." Journal of Organometallic Chemistry 301, no. 2 (1986): 153–60. http://dx.doi.org/10.1016/0022-328x(86)80006-7.

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10

Griesbaum, Karl, and Ashis R. Bandyopadhyay. "Anomalous ozone degradations of 1-chloro substituted conjugated dienes in methanol." Canadian Journal of Chemistry 65, no. 3 (1987): 487–90. http://dx.doi.org/10.1139/v87-084.

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Diozonolyses in methanol of (E)-4-chloro-2,3-dimethyl-1,3-hexadiene (4a) and of (4E)-5-chloro-3,4-dimethyl-2,4-heptadiene (4b) resulted in complete cleavage of the double bonds and of the single bonds of the respective diene systems. The course of these anomalous cleavage reactions has been established by step-wise ozonolyses of these dienes, and by the identification of labile methoxy hydroperoxides as intermediates.

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11

Lindsay, T., P. M. Walker, D. A. Mickle, and A. D. Romaschin. "Measurement of hydroxy-conjugated dienes after ischemia-reperfusion in canine skeletal muscle." American Journal of Physiology-Heart and Circulatory Physiology 254, no. 3 (1988): H578—H583. http://dx.doi.org/10.1152/ajpheart.1988.254.3.h578.

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Recent studies have suggested that oxygen-derived free radicals are involved in the reperfusion injury of ischemic skeletal muscle. Although postischemic necrosis and increased vascular permeability have been attenuated with the addition of free radical scavengers, no unequivocal chemical evidence for free radical injury in skeletal muscle is available. The purpose of this study was to identify products of free radical-mediated membrane injury by isolation of lipid oxidation products (hydroxy-conjugated dienes) from postischemic skeletal muscle. The bilateral canine gracilis muscle model was u

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12

Kanemaguire, LAP, SG Pyne, AFH Siu, BW Skelton, and AH White. "Synthesis, Characterization and Reactions of the Chiral Transfer Agent Dicarbonyl(triphenylphosphine)-[(4r)-phenyl-(1'r)-(1'-phenylethyl)-1-azabuta-1,3-diene]iron(0)." Australian Journal of Chemistry 49, no. 6 (1996): 673. http://dx.doi.org/10.1071/ch9960673.

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The synthesis and room temperature single-crystal X-ray structural characterization of the title compound [( PhCH =CHCH= NCHMePh )Fe(CO)2(PPh3)] are described, the first optically pure 1-azabuta-1,3-diene adduct of iron(0) to be so recorded. Crystals are orthorhombic, P212121, a 20.197(6), b 14.09(1), c 11.094(5) Ǻ, Z 4; conventional R on |F| was 0.061 for 2217 independent 'observed' (I> 3σ(I)) reflections. This compound has been employed to transfer the Fe(CO)2(PPh3) moiety to cyclic 1,3-dienes to give new complexes, including the first example of optically active dicarbonyl ( triphenyl -

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13

Seekamp, A., C. Lalonde, D. G. Zhu, and R. Demling. "Catalase prevents prostanoid release and lung lipid peroxidation after endotoxemia in sheep." Journal of Applied Physiology 65, no. 3 (1988): 1210–16. http://dx.doi.org/10.1152/jappl.1988.65.3.1210.

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We determined the effect of H2O2 on both the physiological and biochemical lung changes seen in the adult sheep after endotoxin. Fourteen unanesthetized adult sheep with chronic lung lymph fistula were given Escherichia coli endotoxin (1 microgram/kg) over 30 min. Seven sheep were given catalase (32,500 U/kg body wt) as an intravenous bolus 30 min before endotoxin. Four sheep were given catalase alone. Oxidant lung changes were measured using arterial plasma conjugated dienes and lung tissue malondialdehyde (MDA) content, both reflecting the lipid peroxidation process. Animals were killed 5 h

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14

Ali, Amjad, Muhammad Khurram Tufail, Muhammad Imran Jamil, et al. "Comparative Analysis of Ethylene/Diene Copolymerization and Ethylene/Propylene/Diene Terpolymerization Using Ansa-Zirconocene Catalyst with Alkylaluminum/Borate Activator: The Effect of Conjugated and Nonconjugated Dienes on Catalytic Behavior and Polymer Microstructure." Molecules 26, no. 7 (2021): 2037. http://dx.doi.org/10.3390/molecules26072037.

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The copolymerization of ethylene‒diene conjugates (butadiene (BD), isoprene (IP) and nonconjugates (5-ethylidene-2-norbornene (ENB), vinyl norbornene VNB, 4-vinylcyclohexene (VCH) and 1, 4-hexadiene (HD)), and terpolymerization of ethylene-propylene-diene conjugates (BD, IP) and nonconjugates (ENB, VNB, VCH and HD) using two traditional catalysts of C2-symmetric metallocene—silylene-bridged rac-Me2Si(2-Me-4-Ph-Ind)2ZrCl2 (complex A) and ethylene-bridged rac-Et(Ind)2ZrCl2 (complex B)—with a [Ph3C][B(C6F5)4] borate/TIBA co-catalyst, were intensively studied. Compared to that in the copolymerizat

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15

Verner, Jiří, and Milan Potáček. "Aromatic glyoxalimines in criss-cross cycloaddition reactions." Open Chemistry 2, no. 1 (2004): 220–33. http://dx.doi.org/10.2478/bf02476192.

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AbstractAromatic 1,4-diazabuta-1,3-dienes in glacial acetic acid with thiocyanates produce via criss-cross cycloaddition reactions the corresponding perhydroimidazo[4,5-d]imidazole-2,5-dithiones. When a mixture of thiocyanate and cyanate in a proper ratio was reacted together, nonsymmetrical 5-thioxo-perhydroimidazo[4,5-d]imidazole-2-ones were isolated. With cyanates substituted aromatic 1,4-diazabuta-1,3-dienes afforded product of acetic acid addition to primary formed 1,3-dipole intermediate 5-(4-substituted phenylamino)-3-(4-substituted phenyl)-2-oxoimidazolidin-4-yl acetate.

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16

Park, Young Tae, Stephen Q. Zhou, Georges Manuel, and William P. Weber. "Synthesis and polymerization of 5-silaspiro[4.4] nona-2,7-dienes." Macromolecules 24, no. 11 (1991): 3221–26. http://dx.doi.org/10.1021/ma00011a028.

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17

James, Philippe, Kurt Schenk, and Yannick Landais. "Radical-Mediated 5-Exo-TrigCyclizations of 3-Silylhepta-1,6-dienes." Journal of Organic Chemistry 71, no. 9 (2006): 3630–33. http://dx.doi.org/10.1021/jo060024+.

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18

Shea, K. J., and L. D. Burke. "Bridgehead dienes. Thermal generation of the bicyclo[3.3.1]nona-1(2),4(5)-diene (ZZ) ring system." Tetrahedron Letters 28, no. 7 (1987): 735–38. http://dx.doi.org/10.1016/s0040-4039(01)80975-8.

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19

Brown, Ronald W., Farzad Zamani, Michael G. Gardiner, Haibo Yu, Stephen G. Pyne, and Christopher J. T. Hyland. "Divergent Pd-catalyzed cross-coupling of allenyloxazolidinones to give chiral 1,3-dienes and vinyloxazolidinones." Chemical Science 10, no. 39 (2019): 9051–56. http://dx.doi.org/10.1039/c9sc03215k.

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20

Dayana, Kunjumon, and Megaravalli R. Manasa. "Antioxidant activity of ethanolic extract of Calotropis procera root in wistar rats." International Journal of Basic & Clinical Pharmacology 7, no. 11 (2018): 2107. http://dx.doi.org/10.18203/2319-2003.ijbcp20184212.

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Background: Free radicals generated as by-products of metabolism can cause damage to lipids, proteins and DNA. They are scavenged by endogenous antioxidant mechanisms. But when these mechanisms are overwhelmed, free radicals can cause toxicity. There is a need to identify new antioxidant compounds. Hence the current study was undertaken to assess the antioxidant activity of ethanolic extract of Calotropis procera roots in Wistar rats.Methods: Wistar rats were divided into 4 groups. Group 1 (control) were administered vehicle. Group 2 received DMBA (30mg/kg BW, single dose) intraperitoneally on

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21

Auner, Norbert, and Erika Penzenstadler. "Silaheterocyclen, XVII / Silaheterocycles, XVII." Zeitschrift für Naturforschung B 47, no. 6 (1992): 795–804. http://dx.doi.org/10.1515/znb-1992-0607.

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The silene 2 is formed by reacting 2-chloro-1,3-bis(trimethylsilyl)-2-vinyl-1,3-diaza-2-silacyclopentane (5) with LiBut in n-pentane in the temperature range from -10 to +10°C. The reaction primarily leads to the corresponding a-lithio adduct 6 by addition of the Li-organyl to the vinyl group of 5; subsequent 1,2-LiCl elimination yields 2 as an intermediate. 2 can be trapped by polar reagents Me3SiX (X = OMe, OSO2CF3) as well as by organic dienes which add across the Si=C bond; in the absence of trapping agents, trisilacyclohexane 7 is isolated. The cycloaddition behaviour of 2 is best describ

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22

Goldfogel, Matthew J., and Simon J. Meek. "Diastereoselective synthesis of vicinal tertiary and N-substituted quaternary stereogenic centers by catalytic hydroalkylation of dienes." Chemical Science 7, no. 7 (2016): 4079–84. http://dx.doi.org/10.1039/c5sc04908c.

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23

Enlisnawati, Enlisnawati. "UPAYA MENINGKATKAN HASIL BELAJAR SISWA DALAM PEMBELAJARAN OPERASI PENGURANGAN BILANGAN CACAH MELALUI BLOK DIENES DI KELAS II SDN 23 VII KOTO SUNGAI SARIK KABUPATEN PADANG PARIAMAN TAHUN PELAJARAN 2015/2016." Unes Journal of Education Scienties 1, no. 1 (2017): 057. http://dx.doi.org/10.31933/ujes.1.1.057-071.2017.

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Tujuan penelitian ini adalah untuk mendeskripsikan penggunaan Blok Dienes dalam meningkatkan pemahaman siswa terhadap operasi pengurangan bilangan cacah dan utuk megetahui bagaimana peningkatan pemahaman siswa tehadap operasi pengurangan bilangan cacah dengan penggunaan Blok Dienes di kelas II SDN 04 Sintoga Kabupaten Padang Pariaman. Penelitian ini didasar kenyataaan di sekolah bahwa dalam penyampaian pembelajaran, konsep guru belum menggunakan alat peraga yang sesuai dengan materi, ketersediaannya terbatas dan guru kurang mengerti cara menggunakannya. Akibatnya siswa sulit memahami konsep-ko

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24

Majer, Roberta, Olga Konechnaya, Ignacio Delso, et al. "Highly diastereoselective 1,3-dipolar cycloadditions of chiral non-racemic nitrones to 1,2-diaza-1,3-dienes: an experimental and computational investigation." Org. Biomol. Chem. 12, no. 44 (2014): 8888–901. http://dx.doi.org/10.1039/c4ob01371a.

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25

Banwell, MG, and JH Knight. "The Reaction of Tetrachlorocyclopropene With Trimethylsiloxybuta-1,3-dienes: A One-Pot Diels-Alder Route to Trichlorotropones and Trichlorotropolones." Australian Journal of Chemistry 46, no. 12 (1993): 1861. http://dx.doi.org/10.1071/ch9931861.

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26

Ward, Dale E., Thomas E. Nixey, Yuanzhu Gai, Matthew J. Hrapchak, and M. Saeed Abaee. "Intramolecular Diels–Alder reactions of 2H-thiopyran dienes." Canadian Journal of Chemistry 74, no. 7 (1996): 1418–36. http://dx.doi.org/10.1139/v96-160.

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A systematic survey of IMDA reactions of 4-[tris(2-methylethyl)silyl]oxy-2H-thiopyran derivatives with potential dienophiles tethered at the C-2, C-3, C-5, and C-6 positions is presented. Cycloaddition was not observed with a C3 or C4 tether and an unactivated terminal olefin as dienophile. IMDA adducts could be obtained when dienophiles activated by a carbomethoxy group were employed. Compounds having the activated dienophile attached via a C3 tether to C-2 of the 2H-thiopyran gave adducts with high stereoselectivity. Substrates having the dienophile attached to C-3 with a C3 or C4 tether cyc

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27

Alajarin, Mateo, Jose Cabrera, Pilar Sanchez-Andrada, Delia Bautista, and Aurelia Pastor. "5-Alkenylthiazoles as In-Out Dienes in Polar [4+2] Cycloaddition Reactions." European Journal of Organic Chemistry 2013, no. 33 (2013): 7500–7511. http://dx.doi.org/10.1002/ejoc.201300925.

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28

Wrackmeyer, Bernd, Roland Köster, and Günter Seidel. "Notizen: Tricarbonyliron Complexes - Observation of 13C(CO) NMR Signals via Polarization Transfer." Zeitschrift für Naturforschung B 50, no. 7 (1995): 1127–29. http://dx.doi.org/10.1515/znb-1995-0726.

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Improvements in the detection of 13C(CO) resonances by using polarization transfer techniques, based on long-range coupling constants nJ(13C(CO)1H) = 1 ±0.1 Hz (n > 3), are reported. Coupling constants between 13C(CO) and other rare spin-1/2 nuclei have been observed, and longrange 13C(CO)-1H coupling have been traced by two-dimensional (2D ) 13C/1H heteronuclear shift correlations (HETCOR). Seven tricarbonyliron complexes 1 to 5 serve as examples in which the [Fe(CO)3] fragment is linked to cyclic dienes (siloles: 1a, b; 1,1′-spirobisilole: 2), and to cyclic heterodienes derived from subst

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29

Auner, Norbert, and Erika Penzenstadler. "Silaheterocyclen, XVIII Synthese und Cycloadditionsreaktionen C-silylmodifizierter aminocyclischer Silaethene [1] / Silaheterocycles, XVIII Synthesis and Cycloaddition Reactions of C-Silyl Modified Amino Cyclic Silenes [1]." Zeitschrift für Naturforschung B 47, no. 6 (1992): 805–13. http://dx.doi.org/10.1515/znb-1992-0608.

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The reaction of 2-chloro-1,3-bis(trimethylsilyl)-2-(1′-trimethylsilyl-ethenyl)-1,3-diaza-2-silacyclopentane (5) and LiBu leads to the α-lithio adduct 8 which can be trapped by Me3Sitriflate to give 13b, and is a useful silene precursor. Subsequent 1,2-LiCl elimination yields 2 as an intermediate, which does not cyclodimerise giving a 1,3-disilacyclobutane, but can be trapped by Me3SiOMe and suitable dienes which add across the Si=C bond. In contrast to silene 1, which favours the [2+2] addition, 2 exclusively forms the Diels-Alder isomers with 2-methyl-1,3-butadiene and 2,3-dimethyl-1,3-butadi

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30

Ward, Dale E., Yuanzhu Gai, and Wajdi M. Zoghaib. "Diels–Alder reactions of activated 2H-thiopyrans." Canadian Journal of Chemistry 69, no. 10 (1991): 1487–97. http://dx.doi.org/10.1139/v91-220.

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The Diels–Alder reactivity of various 2H-thiopyrans bearing electron-donating substituents has been investigated. The approximate order of reactivity among the 2H-thiopyrans studied was 4,6-disubstituted [Formula: see text] 5-substituted > 4-substituted, 3,5-disubstituted [Formula: see text] 3-substituted. Good yields of predominantly endo adducts are obtained with reactive dienophiles. With less reactive dienophiles, reactions are much slower and yields are attenuated due to the competing thermal decomposition of the dienes under the reaction conditions. The adducts obtained are equivalent

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31

Chang, Chu-An, Stefan Gürtzgen, Erik P. Johnson та K. Peter C. Vollhardt. "Stoichiometric and Catalytic (η 5-Cyclopentadienyl)cobalt-Mediated Cycloisomerizations of Ene-Yne-Ene Type Allyl Propargyl Ethers". Synthesis 52, № 03 (2019): 399–416. http://dx.doi.org/10.1055/s-0039-1690727.

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The complexes CpCoL2 (Cp = C5H5; L = CO or CH2=CH2) mediate the cycloisomerizations of α,δ,ω-enynenes containing allylic ether linkages to 3-(oxacyclopentyl or cycloalkyl)furans via the intermediacy of isolable CpCo-η 4-dienes. A suggested mechanism comprises initial complexation of the triple bond and one of the double bonds, then oxidative coupling to a cobalt-2-cyclopentene, terminal double bond insertion to assemble a cobalta-4-cycloheptene, β-hydride elimination, and reductive elimination to furnish a CpCo-η 4-diene. When possible, the cascade continues through cobalt-mediated hydride shi

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32

Block, E. R., J. M. Patel, and D. Edwards. "Mechanism of hypoxic injury to pulmonary artery endothelial cell plasma membranes." American Journal of Physiology-Cell Physiology 257, no. 2 (1989): C223—C231. http://dx.doi.org/10.1152/ajpcell.1989.257.2.c223.

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We exposed monolayer cultures of pulmonary artery endothelial cells or plasma membranes derived from these cells to hypoxic (0 and 5% O2) and normoxic (20% O2; control) conditions and measured cellular contents of malondialdehyde and conjugated dienes, plasma membrane fluidity and lipid composition, and plasma membrane-dependent transport of 5-hydroxytryptamine (5-HT). Hypoxia caused significant increases in malondialdehyde and conjugated dienes, in fluidity, and in 5-HT transport. Hypoxia also caused a significant decrease in plasma membrane total phospholipids and a marked increase in plasma

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33

Yavari, Issa, and Farough Nasiri. "Synthesis of 1-alkylamino-5-hydroxy-5-phenyl-2,3,4-tribenzoylcyclopenta-1,3-dienes in the THF/H2O system." Mendeleev Communications 16, no. 5 (2006): 275–76. http://dx.doi.org/10.1070/mc2006v016n05abeh002284.

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34

Khlebnikov, Alexander F., Mikhail S. Novikov, Yelizaveta G. Gorbunova, et al. "Isoxazolium N-ylides and 1-oxa-5-azahexa-1,3,5-trienes on the way from isoxazoles to 2H-1,3-oxazines." Beilstein Journal of Organic Chemistry 10 (August 14, 2014): 1896–905. http://dx.doi.org/10.3762/bjoc.10.197.

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Theoretical and experimental studies of the reaction of isoxazoles with diazo compounds show that the formation of 2H-1,3-oxazines proceeds via the formation of (3Z)-1-oxa-5-azahexa-1,3,5-trienes which undergo a 6π-cyclization. The stationary points corresponding to the probable reaction intermediates, isoxazolium N-ylides, were located by DFT calculations at the B3LYP/6-31G(d) level only for derivatives without a substituent in position 3 of the isoxazole ring. These isoxazolium N-ylides are thermodynamically and kinetically very unstable. According to the calculations and experimental result

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35

Cai, Mingzhong, Haigen Li, and Wenyan Hao. "Stereoselective synthesis of (3E)-2-stannyl-1,3-dienes via palladium catalysed cross-coupling reactions." Journal of Chemical Research 2005, no. 2 (2005): 103–4. http://dx.doi.org/10.3184/0308234054497209.

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Hydrozirconation of terminal alkynes 1 gives (E)-alkenylzirconium complexes 3, which when cross-coupled with α-iodoethenylstannanes 4 in the presence of [Pd(PPh3)4] catalyst afford stereoselectively (3E)-2-stannyl-1,3-dienes 5 in good yields.

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36

Rösch, Wolfgang, та Manfred Regitz. "Notizen: Phosphorverbindungen ungewöhnlicher Koordination, 12. Diels-Alder-Reaktionen mit tBu–C ≡ P – ein ergiebiger Weg zu λ3-Phosphininen/ Phosphorus Compounds with Unusual Coordination, 12. Diels-Alder Reactions with tB u–C≡ P–a Lucrative Access to λ3-Phosphinines". Zeitschrift für Naturforschung B 41, № 7 (1986): 931–34. http://dx.doi.org/10.1515/znb-1986-0723.

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AbstractDiels-Alder reactions of the phosphaalkyne 4 with the cyclic 1,3-dienes 5 generate the adducts 6 which decompose spontaneously under elimination of “X ” to yield the λ3-phosphinines 7. The bicyclic 9 decomposes into 7b on flash pyrolysis

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37

Kayran, Ceyhan, Saim Özkar, and Vagif M. Akhmedov. "Photo-Induced Chromiumcarbonyl Catalyzed Hydrosilylation of Conjugated Dienes with Triethylsilane: The Solvent Effect." Zeitschrift für Naturforschung B 58, no. 7 (2003): 644–48. http://dx.doi.org/10.1515/znb-2003-0707.

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Photocatalytic hydrosilylation of conjugated dienes (1,3-butadiene, 2-methyl-1,3-butadiene, 2,3- dimethyl-1,3-butadiene, trans-1,3-pentadiene) with triethylsilane was studied by using Cr(CO)5L (L = CO, P(CH3)3, P(OCH3)3, P(C6H5)3, P(C6H11)3, NC5H5) in two very different solvents, toluene and tetrahydrofuran, for comparison with the results found in n-hexane. In toluene, the photocatalytic hydrosilylation yields the same products as those in n-hexane, with the exception of trans- 1,3-pentadiene which gives cis-1-triethylsilyl-2-pentene as the sole product. However, each of the precursor complex

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38

Edwards, Oliver E., Austin M. Greaves, and Wing-Wah Sy. "Reactions of 1,2-dehydropyrrolidin-5-one with 1,3-dienes. Synthesis of dl-gephyrotoxin 223AB." Canadian Journal of Chemistry 66, no. 5 (1988): 1163–72. http://dx.doi.org/10.1139/v88-191.

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Evidence is presented that the regiospecific and often stereospecific pseudo-Diels–Alder reactions of 1,3-dienes with N-acyl immonium salts, derived from 5-ethoxy-2-pyrrolidinone, are stepwise reactions. 6,7-Dehydroindolizidinones, unsaturated lactam esters, and new indene and furan derivatives are described. A synthesis of dl-gephyrotoxin 223AB (indolizidine 223AB) from trans-1,3-heptadiene was achieved.

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39

Baskaran, Sundarababu, Imadul Islam, Padma S. Vankar, and Srinivasan Chandrasekaran. "Heterogeneous permanganate oxidation of 1,5-dienes: a novel synthesis of 5-substituted butanolides." Journal of the Chemical Society, Chemical Communications, no. 8 (1992): 626. http://dx.doi.org/10.1039/c39920000626.

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40

Crossley, Daniel L., Christopher D. Gabbutt, B. Mark Heron, Paul Kay, and Martin Mogstad. "Synthesis and photochromic properties of spiro[naphthopyran-7′H-benzocyclohepta-5′,8′-dienes]." Dyes and Pigments 95, no. 1 (2012): 62–68. http://dx.doi.org/10.1016/j.dyepig.2012.03.031.

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41

Burger, Klaus, Norbert Sewald, Erasmus Huber, and Ralph Ottlinger. "Reaktionen 4,4-Bis(trifluormethyl)-substituierter Heterodiene mit Alkinen / Reactions of 4,4-Bis(trifluoromethyl) Substituted Heterodienes with Alkynes." Zeitschrift für Naturforschung B 44, no. 10 (1989): 1298–312. http://dx.doi.org/10.1515/znb-1989-1026.

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4,4-Bis(trifluoromethyl) substituted 1-oxa-3-azabuta-1,3-dienes (1) and alkynes react to give open-chain trifluoromethyl substituted N-propargylic amides (4), 4H-1,3-oxazines (5) and 2-oxazolines (6, 7), respectively. The selectivity of the reaction can be controlled effectively by the reaction conditions used.

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42

Cameron, Donald W., Chee-Yong Gan, Peter G. Griffiths, and Judy A. Pattermann. "Synthesis of Highly Oxygenated Anthraquinones from Chamaecrista greggii." Australian Journal of Chemistry 51, no. 5 (1998): 421. http://dx.doi.org/10.1071/c97211.

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Four isomeric anthraquinones (2)–(5) have been synthesized for the first time, by cycloaddition involving the new dienes (8) and (9). Their spectroscopic properties have been compared together and with data for two natural anthraquinones reported from Chamaecrista greggii. The assigned structure (2) was thereby supported for one of the natural isomers. The other isomer, previously formulated as (3), did not correspond to any of the synthesized compounds [(2)–(5)].

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43

Velasco-Rubio, Álvaro, Jesús A. Varela, and Carlos Saá. "Palladium-Catalyzed [5 + 2] Heteroannulation of Phenethylamides with 1,3-Dienes to Dopaminergic 3-Benzazepines." Organic Letters 22, no. 9 (2020): 3591–95. http://dx.doi.org/10.1021/acs.orglett.0c01053.

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44

Larock, Richard C., Yao Wang, Xiaoyang Dong, and Tuanli Yao. "Synthesis of C-5 substituted nucleosides via palladium-catalyzed coupling of dienes and amines." Tetrahedron 61, no. 48 (2005): 11427–39. http://dx.doi.org/10.1016/j.tet.2005.08.065.

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45

Alajarin, Mateo, Jose Cabrera, Pilar Sanchez-Andrada, Delia Bautista, and Aurelia Pastor. "ChemInform Abstract: 5-Alkenylthiazoles as In-Out Dienes in Polar [4 + 2] Cycloaddition Reactions." ChemInform 45, no. 18 (2014): no. http://dx.doi.org/10.1002/chin.201418135.

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46

Leigh, William J., J. Alberto Postigo, and K. C. Zheng. "Cyclobutene photochemistry. Adiabatic photochemical ring opening of alkylcyclobutenes." Canadian Journal of Chemistry 74, no. 6 (1996): 951–64. http://dx.doi.org/10.1139/v96-105.

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The photochemistry of the cis and trans isomers of a series of dimethylbicyclo[n 2.0]alk-(n + 2)-enes (n = 2–5) (bicyclic cyclobutene derivatives in which the C=C bond is shared by the two rings) in pentane solution is described. Irradiation of these compounds using monochromatic 193- or214-nm light sources results in ring opening to yield the corresponding 1,2-bis(1-ethylidene)cycloalkanes (C4–C7) in high chemical and quantum yields. In all cases, the reaction proceeds with a high (70–90%) degree of disrotatory stereoselectivity. Quantum yields for direct cis,trans photoisomerization of the i

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47

Kreiter, Cornelius G., Wolfgang Conrad та Reiner Exner. "Gehinderte Ligandbewegungen in Übergangsmetallkomplexen, XLII [1]: Photoreaktionen von Hexacarbonyl-μ-η5:5-fulvalen-dimolybdän und -diwolfram mit konjugierten Dienen / Hindered Ligand Movements in Transition Metal Complexes, XLII [1]: Photoreactions of Hexacarbonyl-μ–η5:5-fulvalene-dimolybdenum and -ditungsten with Conjugated Dienes". Zeitschrift für Naturforschung B 48, № 11 (1993): 1635–50. http://dx.doi.org/10.1515/znb-1993-1124.

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Photochemical reactions of hexacarbonyl-μ-η5:5-fulvalene-dimolybdenum (1) with 1,3-butadiene (a), 2-methyl-1,3-butadiene (b), E-1,3-pentadiene (c), 2,3-dimethyl-1,3-butadiene (d), and E-3-methyl-1,3-pentadiene (e) yield the corresponding tetracarbonyl-η4-s-cisdiene-μ-η5:5-fulvalene-dimolybdenum complexes 3a-3e. In addition to 3a also η4-s-trans1,3-butadiene-tetracarbonyl-μ-η5:5-fulvalene-dimolybdenum (4) is formed. Similarily hexacarbonyl-μ-η5:5-fulvalene-ditungsten (2) forms with a and b tetracarbonyl-η4-s-cis-diene-μ-η5:5-fulvalene-ditungsten (5a, 5b) and bis(η4-s-cis-1,3-butadiene)-dicarbon

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48

Kreiter, Cornelius G., та Klaus Lehr. "Photochemische Reaktionen von Übergangsmetall-Organyl-Komplexen mit Olefnen, VI. Reaktionen von Tricarbonyl-η5-2,4-cyclohexadienyl-mangan mit konjugierten Dienen / Photochemical Reactions of Transition Metal Organyl Complexes with Olefins, VI. Reactions of Tricarbonyl (η5-2,4-cyclohexadienyl)manganese with Conjugated Dienes". Zeitschrift für Naturforschung B 46, № 10 (1991): 1377–83. http://dx.doi.org/10.1515/znb-1991-1016.

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Tricarbonyl-η5-2,4-cyclohexadien-1-yl-manganese (1) was reacted photochemically at 253 K with simple conjugated dienes. Four different types of products were obtained, depending upon the dienes. With 1,3-butadiene (A) dicarbonyl-η4:3-1-(3-buten-1,2-diyl)-2,4-cyclohexadiene-manganese (2A) is isolated. 2-Methyl-1,3-butadiene (B) yields the methyl-substituted diastereomeric dicarbonyls 2B, 2B′, the [4+5]-cycloadduct tricarbonyl-η3:2-3-methyl-bicyclo-[4.3.1]-3,8-decadien-7-yl-manganese (3B) and tetracarbonyl-η3-4-methylene-bicyclo[4.3.1]-8-decen-3-yl-manganese (4B) with an exocyclically coordinate

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49

Cabrera, Aivlé, Diana Henríquez, Thamara Bustos, Julio Herrera, and Neudo Urdaneta. "Inhibition of Functionalized 1,3-Dienes against Trypanosoma cruzi." Zeitschrift für Naturforschung C 60, no. 5-6 (2005): 415–20. http://dx.doi.org/10.1515/znc-2005-5-609.

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Six functionalized 1,3-dienes were synthesized using cross-coupling reactions, catalyzed by palladium complexes, between alkenylboronic acids and α-bromo-α,β-unsaturated carbonylic compounds. Their cytotoxicity against epimastigotes of Trypanosoma cruzi and fibroblastic Vero cells was evaluated, using concentrations ranging from 100 μm to 2.5 mм in experiments with three incubation times (4, 8 and 16 h). These tests were performed using MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] colorimetric bioassays and its further reduction to formazan, according to the viability of

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50

Pyne, SG, B. Dikic, PA Gordon, BW Skelton, and AH White. "Asymmetric\ Synthesis of Chiral Cyclic Amino Acids by Diels-Alder Reactions of (2S)- and (2R)-4-Methyleneoxazolidin-5-ones." Australian Journal of Chemistry 46, no. 1 (1993): 73. http://dx.doi.org/10.1071/ch9930073.

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The synthesis of chiral (2S)- and (2R)-4-methyleneoxazolidin-5-ones, in high enantiomeric purity from (S)-S- methylcysteine, and their highly exo-selective Diels -Alder reactions with cyclic dienes are described. (1R,2S,4S)-2-Aminobicyclo[2.2.1]heptane-2-carboxylic acid has been prepared in 92% e.e. by these methods. A number of the products have been characterized by single-crystal X-ray methods, and their structure systematics examined.

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