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Published: 10 December 2022

Last updated: 28 January 2023

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1

Spino, Claude, and Jason Crawford. "2-Carbomethoxy-1,3-butadiene: an electronically activated diene in [4 + 2] cycloadditions with electron-deficient dienophiles." Canadian Journal of Chemistry 71, no. 7 (July 1, 1993): 1094–97. http://dx.doi.org/10.1139/v93-145.

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Cross Diels–Alder reactions between 2-carbomethoxy-1,3-butadiene 1 and electron-rich dienes were carried out. It was found that diene 1 had a higher reactivity than even the well-known Danishefsky diene in its Diels–Alder cycloaddition with electron-deficient dienophiles. In addition, (Z)-1-methylthio-3-carbomethoxy-1,3-butadiene 11 was found to have a higher reactivity than (Z)-1-methylthio-1,3-butadiene and (Z)-2-carbomethoxy-1,3-hexadiene, while both (E)- and (Z)-1,2-(bis)-carbomethoxy-1,3-butadiene 14 reacted efficiently with maleic anhydride to give the corresponding cy-cloadduct 15.

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2

Ibis, Cemil, M. Cigdem Sayil, and N. Gulsah Deniz. "1,3,4,4-Tetrachloro-4-(4-chlorophenylsulfanyl)-2-nitrobuta-1,3-diene." Acta Crystallographica Section E Structure Reports Online 62, no. 2 (January 27, 2006): o800—o801. http://dx.doi.org/10.1107/s1600536806001838.

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3

Cosmo, R., and S. Sternhell. "Synthesis of 4-(4'-Chlorophenyl)-5-Phenyl-1,2-Dihydronaphthalene." Australian Journal of Chemistry 40, no. 9 (1987): 1499. http://dx.doi.org/10.1071/ch9871499.

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BF3-catalysed cyclization reactions of 1-(biphenyl-2'-y1)- 1-(4″-chlorophenyl)but-3-en-1-ol yielded none of the desired title compound but only 9-(4'-chloropheny1)-10-ethylphenanthrene and 9-allyl-9-(4'-chlorophenyl) fluorene by alternative cyclization pathways. Corresponding cyclization of the related diene 1-(biphenyl-2'-yl)-1-(4″-chlorophenyl)buta-1,3-diene also failed to yield the desired title compound but gave instead the unexpected product 9-(4'-chlorophenyl) phenanthrene through a novel mechanism. Flash pyrolysis of l-(biphenyl-2'-yl)-l-(4″-chlorophenyl)buta-1,3-diene gave the desired compound as a minor constituent of the reaction mixture, the major constituent being 4-(biphenyl-2'-yl)-7-chloro- 1,2-dihydronaphthalene.

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4

Onul, Nihal, Onur Ertik, Neşe Mermer, and Refiye Yanardag. "Synthesis and Biological Evaluation of S-Substituted Perhalo-2-nitrobuta-1,3-dienes as Novel Xanthine Oxidase, Tyrosinase, Elastase, and Neuraminidase Inhibitors." Journal of Chemistry 2018 (2018): 1–11. http://dx.doi.org/10.1155/2018/4386031.

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S-substituted perhalo-2-nitrobuta-1,3-dienes 3a, b were synthesized by the reaction of polyhalo-2-nitrobuta-1,3-dienes 1a, b with allyl mercaptan. 1-(2,3-Dibromopropanethio)-4-bromo-1,3,4-trichloro-2-nitrobuta-1,3-diene 4 was obtained from the addition of bromine to S-substituted polyhalo-2-nitrobuta-1,3-diene 3b in carbon tetrachloride. Sulfoxides 5a, b, and 6 were obtained from the reaction of thiosubstituted polyhalonitrobutadienes 3a, b, and 4 with m-CPBA in CHCl3. The structures of the new compounds were determined by spectroscopic data (FTIR, 1H NMR, 13C NMR, MS). These compounds exhibited antixanthine oxidase, antityrosinase, antielastase, and antineuraminidase activities.

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5

Ibis, Cemil, and Zeliha Gokmen. "3,4,4-Trichloro-1-(4-chlorophenylsulfanyl)-1-[4-(2-fluorophenyl)piperazinyl]-2-nitrobuta-1,3-diene." Acta Crystallographica Section E Structure Reports Online 62, no. 7 (June 21, 2006): o2932—o2933. http://dx.doi.org/10.1107/s1600536806022483.

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6

Tomé, A. C., P. M. O'Neill, R. C. Storr, and J. A. S. Cavaleiro. "2-Methyl-5,6-dimethylenepyrimidin-4-one: A Novel Diene." Synlett 1993, no. 05 (1993): 347–48. http://dx.doi.org/10.1055/s-1993-22450.

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7

Tomé, A. C., P. M. O'Neill, R. C. Storr, and J. A. S. Cavaleiro. "2-Methyl-5,6-dimethylenepyrimidin-4-one: A Novel Diene." Synlett 1993, no. 06 (1993): 397–98. http://dx.doi.org/10.1055/s-1993-22468.

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8

Duhamel, Lucette, and Jean-Erick Ancel. "Polyvinylogation reagents : 1-lithio-4-trimethylsiloxy-penta-1,3-diene and 1-lithio-4-ethoxy-2-methyl-buta-1,3-diene." Tetrahedron 48, no. 42 (January 1992): 9237–50. http://dx.doi.org/10.1016/s0040-4020(01)85614-3.

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9

Nesi, Rodolfo, Donatella Giomi, Stefania Turchi, and Paola Paoli. "[4+2]- and [2+4]-cycloaddition processes of 4,5-dicyanopyridazine with 2,3-dimethylbuta-1,3-diene." Tetrahedron 50, no. 30 (January 1994): 9189–94. http://dx.doi.org/10.1016/s0040-4020(01)85385-0.

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10

Kreiter, Cornelius G., Kurt Nist, and 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, no. 5 (May 1, 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 to the other ligands. The interconversion of the o- and u-isomers was studied by dynamic 1H NMR spectroscopy and is explained by an intramolecular ±180° rotation of the diene ligands in the molecular plane. The barriers o f activation ⊿G* 300 are between 57.8 and 61.0 ± 1 kJ/mol.

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11

Narayana, B., M. Sapnakumari, Jerry P. Jasinski, Peter M. Fraiser, and H. S. Yathirajan. "Ethyl 2-amino-6-(4-bromophenyl)-4-(4-fluorophenyl)cyclohexa-1,3-diene-1-carboxylate." Acta Crystallographica Section E Structure Reports Online 69, no. 9 (August 23, 2013): o1473. http://dx.doi.org/10.1107/s1600536813023325.

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12

Nye, Luke, Mark M. Turnbull, and Jan L. Wikaira. "3,4-Dihydroxy-1,6-bis(4-methoxyphenyl)hexa-2,4-diene-1,6-dione, its 4-methylphenyl analogue, and a potassium salt of 2-hydroxy-4-(4-methoxyphenyl)-4-oxobut-2-enoic acid." Acta Crystallographica Section C Crystal Structure Communications 69, no. 11 (October 9, 2013): 1317–21. http://dx.doi.org/10.1107/s0108270113025973.

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Reaction of 4-methoxyacetophenone with diethyl oxalate under basic conditions produced 3,4-dihydroxy-1,6-bis(4-methoxyphenyl)hexa-2,4-diene-1,6-dione, C20H18O6, (1). The molecules lie across a crystallographic inversion centre and intramolecular hydrogen bonding, similar to acetylacetone, is observed, confirming that the molecule is in the di-enol-dione tautomeric form. Additional O—H...O hydrogen bonds link the molecules into chains parallel to thebaxis. The structure is compared with that of redetermined 4-methylphenyl compound 3,4-dihydroxy-1,6-bis(4-methylphenyl)hexa-2,4-diene-1,6-dione, C20H18O4, (2), which crystallizes in a similar fashion. The salt,catena-poly[[μ2-2-hydroxy-4-(4-methoxyphenyl)-4-oxobut-2-enoato-κ3O1,O2:O4][μ2-2-hydroxy-4-(4-methoxyphenyl)-4-oxobut-2-enoic acid-κ2O1:O4]potassium], [K(C11H9O5)(C11H10O5)]n, (3), was isolated as a by-product of the synthesis of (1). The two organic species are linked by a strong hydrogen bond between the carboxylic acid and carboxylate groups. They are further stabilized and linked into a double-chain structureviathe seven-coordinate potassium ion.

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13

Cameron, Donald W., and Ross M. Heisey. "Reaction of Terminally Alkyl-Substituted Oxy Dienes with Tetracyanoethylene and Other Acceptors." Australian Journal of Chemistry 53, no. 3 (2000): 161. http://dx.doi.org/10.1071/ch00035.

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The 4,4-dimethyl-substituted oxy dienes (4), (19) and (20) did not undergo cycloaddition to 1,4-quinonoid dienophiles, for steric reasons, but all reacted with tetracyanoethylene to give [4+2]- or [2+2]-adducts. Unlike the 1-oxy diene (4), the 2- and 3-oxy systems (19) and (20) did not show hydrogen-transfer chemistry towards quinones. The individual components of isomeric pairs of dienes (8), (9) and (19), (21) were differentiated by differing reactivity towards cycloaddition.

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14

Levens, Alison, Changhe Zhang, Lisa Candish, Craig M. Forsyth, and David W. Lupton. "Enantioselective N-Heterocyclic Carbene Catalyzed Diene Regenerative (4 + 2) Annulation." Organic Letters 17, no. 21 (October 20, 2015): 5332–35. http://dx.doi.org/10.1021/acs.orglett.5b02693.

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15

Kinghat, Rodolphe, Hamid Boudiba, Abderrahim Khatyr, Michael Knorr, and Marek M. Kubicki. "4,4-Bis(4-methylphenylsulfanyl)-1,1-diphenyl-2-azabuta-1,3-diene." Acta Crystallographica Section E Structure Reports Online 64, no. 2 (January 4, 2008): o370. http://dx.doi.org/10.1107/s1600536807066615.

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16

Ali, Amjad, Muhammad Khurram Tufail, Muhammad Imran Jamil, Waleed Yaseen, Nafees Iqbal, Munir Hussain, Asad Ali, Tariq Aziz, Zhiqiang Fan, and Li Guo. "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 (April 2, 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 copolymerization of ethylene diene, the catalytic activity was more significant in E/P/diene terpolymerization. We obtained a maximum yield of both metallocene catalysts with conjugated diene between 3.00 × 106 g/molMt·h and 5.00 × 106 g/molMt·h. ENB had the highest deactivation impact on complex A, and HD had the most substantial deactivation effect on complex B. A 1H NMR study suggests that dienes were incorporated into the co/ter polymers’ backbone through regioselectivity. ENB and VNB, inserted by the edo double bond, left the ethylidene double bond intact, so VCH had an exo double bond. Complex A’s methyl and phenyl groups rendered it structurally stable and exhibited a dihedral angle greater than that of complex B, resulting in 1, 2 isoprene insertion higher than 1, 4 isoprene that is usually incapable of polymerization coordination. High efficiency in terms of co- and ter- monomer incorporation with higher molecular weight was found for complex 1. The rate of incorporation of ethylene and propylene in the terpolymer backbone structure may also be altered by the conjugated and nonconjugated dienes. 13C-NMR, 1H-NMR, and GPC techniques were used to characterize the polymers obtained.

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17

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 (June 1, 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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18

Fischer, Alfred, George N. Henderson, and Trevor A. Smyth. "Reactions of the 1-hydroxy-1,4-dimethylcyclohexadienyl cation, an intermediate in the solvolysis of 1,4-dimethyl-4-nitrocyclohexa-2,5-dien-1-ol." Canadian Journal of Chemistry 64, no. 6 (June 1, 1986): 1093–101. http://dx.doi.org/10.1139/v86-184.

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Solvolysis of 1,4-dimethyl-4-nitrocyclohexa-2,5-dien-1-ol in mixed aqueous organic solvents gives the diastereomers of 1,4-dimethylcyclohexa-2,5-diene-1,4-diol, 1,4-dimethylcyclohexa-3,5-diene-1,2-diol, 2-nitro-p-xylene, 2,4-dimethylphenol (all derived from the title cation, itself formed by ionization of the nitro group as nitrite), and 2,5-dimethylphenol. In aqueous methanol the diastereomers of 4-methoxy-1,4-dimethylcyclohexa-2,5-dienol are also obtained. Significant yields of 2,5-dimethylphenol are only obtained on the acid-catalysed further reaction of the dienediol (or the methoxydienol) and involve the intermediate formation of 1,4-dimethylcyclohexa-3,5-diene-1,2-diol. In the absence of added base the acid released in the solvolysis catalyses this reaction and leads to the aromatization of the dienes.

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19

DUHAMEL, L., and J. E. ANCEL. "ChemInform Abstract: Polyvinylogation Reagents: 1-Lithio-4-trimethylsiloxy-penta-1,3-diene and 1-Lithio-4-ethoxy-2-methyl-buta-1,3-diene." ChemInform 24, no. 7 (August 20, 2010): no. http://dx.doi.org/10.1002/chin.199307148.

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20

Lorente, Antonio, Marta Casillas, Pilar Gomez-Sal, and Antonio Manzanero. "2-Azabuta-1,3-diene-4-carbonitriles: stereoselective synthesis and nucleophilic substitution at the carbon–nitrogen double bond." Canadian Journal of Chemistry 74, no. 3 (March 1, 1996): 287–94. http://dx.doi.org/10.1139/v96-032.

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The synthesis of (E)-1-methoxy-2-azabuta-1,3-diene-4-carbonitriles was performed by methylation of N-alkenylamides 9 and 11. The Z isomers were obtained by treatment of (E)-1-methylthio-2-azabuta-1,3-diene-4,4-dicarbonitriles with sodium methoxide in methanol. We also describe the reactions of (E)-1-methylthio-2-azabuta-1,3-diene-4,4-dicarbonitriles with pyrrolidine, which afforded 1-(1-pyrrolidinyl) derivatives 20, 21, and 23. X-ray crystallographic analyses of 21 and 23 established the E stereochemistry of the C—N double bond. Key words: 2-azabuta-1,3-diene-4-carbonitriles: stereoselective synthesis, nucleophilic substitution and X-ray diffraction; N-alkenylamides: methylation.

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21

Ali, Amjad, Jamile Mohammadi Moradian, Ahmad Naveed, Tariq Aziz, Nadeem Muhammad, Chanez Maouche, Yintian Guo, et al. "Progress toward Polymerization Reaction Monitoring with Different Dienes: How Small Amounts of Dienes Affect ansa-Zirconocenes/Borate/Triisobutylaluminium Catalyst Systems." Polymers 14, no. 16 (August 9, 2022): 3239. http://dx.doi.org/10.3390/polym14163239.

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The objectives of this work were to address the fundamental characteristics of ansa-zirconocene catalyzed E/diene copolymerization and E/diene/1-hexene and E/diene/propylene terpolymerizations, and the quantitative relationship between diene structure and polymer chain propagation rate constant in term of quantifiable catalytic active sites. One of the most important but unknown factors in olefins ansa-zirconocene complexes is the distribution of the catalyst between sites actively participating in polymer chain formation and dormant sites. A set of ethylene/dienes copolymerizations, and ethylene/dienes/1-hexene and ethylene/dienes/1-hexene terpolymerizations catalyzed with ansa-zirconocenes/borate/triisobutylaluminium (rac-Et(Ind)2ZrCl2/[Ph3C][B(C6F5)4]/triisobutylaluminium (TIBA) were performed in toluene at 50 °C To determine the active center [C*]/[Zr] ratio variation in the copolymerization of E with different dienes and their terpolymerization with 1-hexene and propylene, each polymer propagation chain ends were quenched with 2-thiophenecarbonyl, which selectively quenches the metal–polymer bonds through acyl chloride. The ethylene, propylene, 1-hexene, and diene composition-based propagation rate constants (kpE, kpP, kp1-H, and kpdiene), thermal (melting and crystalline) properties, composition (mol% of ethylene, propylene, 1-hexene, and diene), molecular weight, and polydispersity were also studied in this work. Systematic comparisons of the proportion of catalytically [Zr]/[C*] active sites and polymerization rate constant (kp) for ansa-zirconocenes catalyzed E/diene, E/diene/1-hexene, and E/diene/propylene polymerization have not been reported before. We evaluated the addition of 1-hexene and propylene as termonomers in the copolymerization with E/diene. To make a comparison for each diene under identical conditions, we started the polymerization by introducing an 80/20 mole ratio of E/P and 0.12 mol/L of 1-hexene in the system. The catalyst behavior against different dienes, 1-hexene, and propylene is very interesting, including changes in thermal properties, cyclization of 1-hexene, and decreased incorporation of isoprene and butadiene, changes in the diffusion barriers in the system, and its effect on kp.

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22

NESI, R., D. GIOMI, S. TURCHI, and P. PAOLI. "ChemInform Abstract: (4 + 2)- and (2 + 4)-Cycloaddition Processes of 4,5-Dicyanopyridazine with 2,3-Dimethylbuta-1,3-diene." ChemInform 25, no. 51 (August 18, 2010): no. http://dx.doi.org/10.1002/chin.199451063.

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23

Murakami, Masahiro, Ryo Minamida, Kenichiro Itami, Masaya Sawamura, and Yoshihiko Ito. "Palladium-catalysed asymmetric [4 + 2] cycloaddition of vinylallene with 1,3-diene." Chemical Communications, no. 23 (2000): 2293–94. http://dx.doi.org/10.1039/b007781j.

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24

Jacquot-Rousseau, Sandrine, Gérard Schmitt, Bernard Laude, Marek M. Kubicki, and Patrice Delarue. "4-Chloro-1,1-diphenyl-3-(1-pyrrolyl)-2-azabuta-1,3-diene." Acta Crystallographica Section E Structure Reports Online 58, no. 4 (March 8, 2002): o364—o365. http://dx.doi.org/10.1107/s1600536802004014.

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25

Mayr, Herbert, and Ulrich W. Heigl. "[4 + 2] Cycloadditions of diphenylketene with a highly substituted 1,3-diene." Journal of the Chemical Society, Chemical Communications, no. 23 (1987): 1804. http://dx.doi.org/10.1039/c39870001804.

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26

TOME, A. C., P. M. O'NEILL, R. C. STORR, and J. A. S. CAVALEIRO. "ChemInform Abstract: 2-Methyl-5,6-dimethylenepyrimidin-4-one: A Novel Diene." ChemInform 25, no. 5 (August 19, 2010): no. http://dx.doi.org/10.1002/chin.199405187.

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27

TOME, A. C., P. M. O'NEILL, R. C. STORR, and J. A. S. CAVALEIRO. "ChemInform Abstract: 2-Methyl-5,6-dimethylenepyrimidin-4-one: A Novel Diene." ChemInform 25, no. 8 (August 19, 2010): no. http://dx.doi.org/10.1002/chin.199408230.

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28

Williams, Richard Vaughan, Michael E. Colvin, Ngoc Tran, Ronald N. Warrener, and Davor Margetic. "Exceptionally Pyramidalized Olefins: A Theoretical Study of the Cyclopropenyl Fused Tricycles Tricyclo[3.2.1.02,4]oct-2(4)-ene, Tricyclo[3.2.1.02,4]octa-2(4),6-diene, Tricyclo[3.2.2.02,4]non-2(4)-ene, and Tricyclo[3.2.2.02,4]nona-2(4),6-diene." Journal of Organic Chemistry 65, no. 2 (January 2000): 562–67. http://dx.doi.org/10.1021/jo991496+.

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29

Nishii, Arata, Hiroshi Takikawa, and Keisuke Suzuki. "2-Bromo-6-(chlorodiisopropylsilyl)phenyl tosylate as an efficient platform for intramolecular benzyne–diene [4 + 2] cycloaddition." Chemical Science 10, no. 13 (2019): 3840–45. http://dx.doi.org/10.1039/c8sc05518a.

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30

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 (January 1987): 735–38. http://dx.doi.org/10.1016/s0040-4039(01)80975-8.

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31

Ibis, Cemil, M. Cigdem Sayil, and F. Ozkok. "3,4,4-Trichloro-1-[4-(2-fluorophenyl)piperazinyl]-1-(n-hexadecylsulfanyl)-2-nitrobuta-1,3-diene." Acta Crystallographica Section E Structure Reports Online 62, no. 3 (February 24, 2006): o1147—o1148. http://dx.doi.org/10.1107/s1600536806005769.

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32

Jin, Fu-qiang, Yuan-yao Xu, and Wei-yuan Huang. "[4 + 2] and [2 + 2] cycloadditions of 1,1-difluoro-2-triphenylsiloxybuta-1,3-diene with electron-deficient alkynes." Journal of Fluorine Chemistry 71, no. 1 (March 1995): 1–4. http://dx.doi.org/10.1016/0022-1139(94)03186-4.

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33

Lee, Gon-Ann, Ai Ni Huang, Chi-Sheng Chen, Yi Ching Li, and Yih-Chyn Jann. "1,2-Bridged Tricyclic Cyclopropenes: Tricyclo[3.2.1.02,4]octa-2(4),6-diene and Tricyclo[3.2.1.02,4]oct-2(4)-ene." Journal of Organic Chemistry 62, no. 10 (May 1997): 3355–59. http://dx.doi.org/10.1021/jo962383i.

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34

Downing, Wendy, Regine Latouche, Carlos A. Pittol, Robert J. Pryce, Stanley M. Roberts, George Ryback, and Julian O. Williams. "[4 + 2], [2 + 2], and Carbene addition reactions involving cyclohexa-3,5-diene-cis-1,2-diol derivatives." Journal of the Chemical Society, Perkin Transactions 1, no. 9 (1990): 2613. http://dx.doi.org/10.1039/p19900002613.

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35

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 - phosphine )(η4-1-methoxycyclohexa-1,3-diene)iron.

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36

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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37

Auner, Norbert, and Erika Penzenstadler. "Silaheterocyclen, XVII / Silaheterocycles, XVII." Zeitschrift für Naturforschung B 47, no. 6 (June 1, 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 described by the two mesomeric formulae (a) and (β), with competitive [4+2] and [2+2] addition routes: While with butadienes and norborna-2,5-diene the [2+2] products are formed mainly in a multiple step reaction via zwitterionic intermediates (1,4 dipoles), the ratio of the [4+2]/[2+2] derivatives from 2 and cyclohexa-1,3-diene becomes nearly equivalent. 2 is thus quite comparable in its reactivity to dichloroneopentylsilene, Cl2Si = CHCH2But.

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38

Golubev, R. V., A. Yu Alekseeva, I. N. Bardasov, Ya S. Kayukov, O. V. Ershov, and O. E. Nasakin. "Reaction of bromomalononitrile with 2-amino-4-arylbuta-1,3-diene-1,1,3-tricarbonitriles." Russian Journal of Organic Chemistry 47, no. 3 (March 2011): 363–65. http://dx.doi.org/10.1134/s1070428011030055.

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39

Matveyev, Yu I., S. V. Sereda, and V. I. Gorbatenko. "Reaction of perchloro-3, 5-diazahepta-2, 4-diene with trimethylsilyl cyanide." Tetrahedron Letters 33, no. 15 (April 1992): 2035–38. http://dx.doi.org/10.1016/0040-4039(92)88134-q.

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40

Ibis, Cemil, and N. Gulsah Deniz. "3,4,4-Trichloro-2-nitro-1-propylsulfanyl-1-(4-thiomorpholinyl)buta-1,3-diene." Acta Crystallographica Section E Structure Reports Online 62, no. 12 (November 3, 2006): o5373—o5374. http://dx.doi.org/10.1107/s1600536806045211.

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41

Jasinski, Jerry P., James A. Golen, S. Samshuddin, B. Narayana, and H. S. Yathirajan. "Ethyl 2-amino-4,6-bis(4-fluorophenyl)cyclohexa-1,3-diene-1-carboxylate." Acta Crystallographica Section E Structure Reports Online 68, no. 3 (February 4, 2012): o585. http://dx.doi.org/10.1107/s160053681200373x.

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42

Levens, Alison, Changhe Zhang, Lisa Candish, Craig M. Forsyth, and David W. Lupton. "ChemInform Abstract: Enantioselective N-Heterocyclic Carbene Catalyzed Diene Regenerative [4 + 2] Annulation." ChemInform 47, no. 12 (March 2016): no. http://dx.doi.org/10.1002/chin.201612038.

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43

Tigchelaar, Andrew, and William Tam. "Iridium-catalyzed intramolecular [4 + 2] cycloadditions of alkynyl halides." Beilstein Journal of Organic Chemistry 8 (October 16, 2012): 1765–70. http://dx.doi.org/10.3762/bjoc.8.201.

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Iridium-catalyzed intramolecular [4 + 2] cycloadditions of diene-tethered alkynyl halides were investigated by using [IrCl(cod)]2 as catalyst, and dppe was found to be the most suitable phosphine ligand for the reaction. No oxidative insertion of the iridium into the carbon–halide bond was observed, and the reactions proceeded to provide the halogenated cycloadducts in good yield (75–94%). These results are the first examples of cycloadditions of alkynyl halides using an iridium catalyst.

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44

Debaerdemaeker, T., B. Stapp, and H. A. Brune. "(1–2:5–6-η-Cycloocta-1,5-diene)(2,4-dinitrophenyl)(4-methoxyphenyl)platinum(II) (1) and (1–2:5–6-η-cycloocta-1,5-diene)(2,4-dinitrophenyl)(4-nitrophenyl)platinum(II) (2)." Acta Crystallographica Section C Crystal Structure Communications 43, no. 3 (March 15, 1987): 473–76. http://dx.doi.org/10.1107/s0108270187095337.

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45

Chang, Chu-An, Stefan Gürtzgen, Erik P. Johnson, and K. Peter C. Vollhardt. "Stoichiometric and Catalytic (η 5-Cyclopentadienyl)cobalt-Mediated Cycloisomerizations of Ene-Yne-Ene Type Allyl Propargyl Ethers." Synthesis 52, no. 03 (October 28, 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 shifts and dissociation of the aromatic furan ring. The outcome of a deuterium labeling experiment supports this hypothesis. The reaction exhibits variable stereoselectivity with a preference for the trans-product (or, when arrested, its syn-Me CpCo-η 4-diene precursor), but is completely regioselective in cases in which the two alkyne substituents are differentiated electronically by the presence or absence of an embedded oxygen. Regioselectivity is also attained by steric discrimination or blocking one of the two possible β-hydride elimination pathways. When furan formation is obviated by such regiocontrol, the sequence terminates in a stable CpCo-η 4-diene complex. The conversion of the cyclohexane-fused substrate methylidene-2-[5-(2-propenyloxy)-3-pentynyl]cyclohexane into mainly 1-[(1R*,3aS*,7aS*)-7a-methyloctahydroinden-1-yl]-1-ethanone demonstrates the potential utility of the method in complex synthesis.

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46

Ovakimyan, M. Zh, A. S. Pogosyan, M. L. Movsisyan, and M. G. Indzhikyan. "Basic hydrolysis of l,4-bis(triphenylphosphonio)buta-1,3-diene dihalides." Russian Chemical Bulletin 59, no. 3 (March 2010): 560–64. http://dx.doi.org/10.1007/s11172-010-0131-2.

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47

Huang, Mengqian, De Bai, Qin Chen, Changbo Zhao, Tianhua Ren, Caijuan Huang, Michael North, and Haibo Xie. "Facile preparation of polycarbonates from bio-based eugenol and 2-methoxy-4-vinylphenol." Polymer Chemistry 11, no. 32 (2020): 5133–39. http://dx.doi.org/10.1039/d0py00291g.

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Polymerization of α,ω-diene functionalized carbonate monomers prepared from bio-based eugenol and 2-methoxy-4-vinylphenol through thiol–ene click and ADMET polymerizations produced polycarbonates with moderate molecular weight satisfactory thermal properties.

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48

Collins, DJ, and NE Krause. "Monoacetals Derived From 12-α-Hydroxyandrosta-1,4-diene-3,17-dione and Androsta-1,4-diene-3,12,17-trione." Australian Journal of Chemistry 41, no. 6 (1988): 985. http://dx.doi.org/10.1071/ch9880985.

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Conversion of 12α-hydroxyandrosta-1,4-diene-3,17-dione (5) into the corresponding 17-cyclic ethylene acetal (1) was accompanied by acid- catalysed attack of ethylene glycol at C3 to give 17,17-ethylenedioxy- 3-(2′-hydroxyethoxy)-1-methylestra-1,3,5(10)-trien-12a-ol (2), which was the major product with prolonged reaction times. Exchange dioxolanation of androsta-1,4-diene-3,12,17-trione (8), prepared by Jones oxidation of (5), gave selectively the 12-monoacetal (9): the regioisomeric 17-monoacetal (4) was obtained by oxidation of the hydroxy acetal (1) with chromium trioxide in pyridine. The trione (8) likewise afforded selectively the 12,12-ethylenedithio acetal (11). Treatment of the trione (8) with p- toluenesulfonic acid in refluxing benzene gave 1-hydroxy-4-methylestra-1,3,5(10)-triene-12,17- dione (7a).

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49

Norris, Derek J., John F. Corrigan, Yan Sun, Nicholas J. Taylor, and Scott Collins. "Functionalization of spirocyclopentadienes using organomolybdenum reagents: approaches to the synthesis of (±)-silphinene." Canadian Journal of Chemistry 71, no. 7 (July 1, 1993): 1029–40. http://dx.doi.org/10.1139/v93-137.

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(η5-Indenyl)molybdenum dicarbonyl complexes of 1,3-dienes, including spirocyclopentadienes, can be cleanly prepared from stoichiometric amounts of 1,3-dienes and [(η5-indenyl)Mo(CO)2(CH3CN)2][BF4] (1) in dichloromethane solution. Nucleophilic addition of lithium dimethylcuprate to the complexed diene occurs in the expected manner to provide η3-allylmolybdenum complexes in high yield. Applications of this chemistry towards the synthesis of (±)-silphinene are described. The allylmolybdenum complexes [(η5-C9H7)(η3-C10H15)Mo(CO)2] (8) and [(η5-C9H7)(η3-C15H23)Mo(CO)2] (33) were structurally characterized by X-ray crystallography. Compound 8: space group P21/n with a = 9.393(1) Å, b = 10.469(2) Å, c = 17.704(2) Å, β = 91.05(1)°, Z = 4, and V = 1770.5(4) Å3. Compound 33: space group P21/c with a = 17.616(4) Å, b = 7.688(2) Å, c = 15.873(2), β = 90.12(2)°, Z = 4, and V = 2149.7(6) Å3.

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50

Depay, Jean Pierre, Jacques Vicens, and Robert Perrin. "Preparation of 4-Chloro-4-Alkylcyclohexa-2, 5-Diene-1-Ones From 4-Alkylphenols by Solid-Gas Reactions." Molecular Crystals and Liquid Crystals 137, no. 1 (July 1986): 45–47. http://dx.doi.org/10.1080/00268948608070911.

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