126696-35-3Relevant academic research and scientific papers
Regioselective 1,4-addition of ammonia to 1-arylalka-1,3-dienes and 1-aryl-4-phenylbuta-1,3-dienes by photoinduced electron transfer
Kojima, Ryuji,Yamashita, Toshiaki,Tanabe, Kimiko,Shiragami, Tsutomu,Yasuda, Masahide,Shima, Kensuke
, p. 217 - 222 (2007/10/03)
The photoamination of 1-arylalka-1,3-dienes 1a-f and 1-aryl-4-phenylbuta-1,3-dienes 1g-k with NH3 in the presence of p-dicyanobenzene (DCB) gives 4-amino-1-arylalk-2-enes 2a-f and 1-amino-1,4-diarylbut-2-enes 2g-k, respectively. The photoamination proceeds by nucleophilic addition of NH3 to the cation radicals of 1+. generated by photoinduced electron transfer to DCB. The regiochemistry of 2 is related to the distribution of the positive charge in 1+. calculated by the PM3-UHF/RHF method, the stability of the aminated radicals formed by the addition of NH3 to 1+. and the stability of the aminated anion formed by the reduction of the aminated radicals by DCB-.. The stabilities of these intermediates are estimated by the calculation of the heat of formation by the PM3-UHF/RHF method. Distributions of the positive charge in 1+. and the stabilities of the aminated anion show a good agreement with the product analysis.
Stereoselective synthesis of all four geometric isomers of internal 1,3-butadienes by the condensation reaction of aldehydes with the γ-trimethylsilyl-substituted allylboranes
Wang, Kung K.,Gu, Yu Gui,Liu, Chin
, p. 4424 - 4431 (2007/10/02)
Hydroboration of 2-(trimethylsilyl)-2,3-pentadiene or 4-(trimethylsilyl)-2,3-octadiene with 9-borabicyclo[3.3.1] nonane or dicyclohexylborane produced the corresponding γ-trimethylsilyl-substituted allylborane which condensed smoothly with aldehydes to afford after elimination of hydroxytrimethylsilane by either basic or acidic workup, a variety of internal 1,3-butadienes Apparently high diastereoselectivity was obtained during the condensation step and therefore allowed an easy control of the geometry of one of the two resulting double bonds by simply employing either basic or acidic workup conditions to promote the Peterson olefination reaction. The geometry of the other double bond could also be controlled by selecting either 9-borabicyclo[3.3.1]nonane or dicyclohexylborane as the hydroborating agent. Consequently, all four geometric isomers of several representative interal 1,3-dienes were synthesized with high isomeric purity by utilizing different combinations of the hydroborating agents and the workup conditions. The [1,3] sigmatropic rearrangement of γ-trimethylsilyl-substituted allylboranes was studied by 1H NMR.
