一系列化合物中,ö -bromomethylbenzylidene甲基-丙二腈(1),二甲基Ô溴甲基benzylidenemalonate(2)和甲基α氰基Ö -bromomethylcinnamate(3)一种由NAD在黑暗中和在照射下被减少(P)H模型,1-苄基-1,4-二氢烟酰胺(BNAH)。发现了两种不同的机理,即一步法氢化物转移(极性途径)和由单电子转移引发的多步序列(SET途径)。根据哈米特取代基常数,13 C NMR化学位移值和循环伏安氧化还原电势及其相关性,讨论了吸电子基团对底物反应性的影响。
Polysiloxane-Supported NAD(P)H Model 1-Benzyl-1,4-dihydronicotinamide: Synthesis and Application in the Reduction of Activated Olefins
作者:Baolian Zhang、Xiao-Qing Zhu、Jin-Yong Lu、Jiaqi He、Peng G. Wang、Jin-Pei Cheng
DOI:10.1021/jo020319x
日期:2003.4.1
A new polysiloxane-supported NAD(P)Hmodel, 1-benzyl-1,4-dihydronicotinamide, was designed and synthesized, which can efficiently reduce many activated olefins under mild conditions. The most advantageous features of this new polysiloxane-supported reductant are (i) easy workup and separation of the reaction products and (ii) good potential for recycling use of the reductant, which makes this new
Mono- vs. dialkylation of carbanions. Effects of absolute and relative acidity of the conjugate carbon acids in selectivity control
作者:Luděk Ridvan、Jiří Závada
DOI:10.1016/s0040-4020(97)00989-7
日期:1997.10
in the reaction of the dibromide 1 with carbanions 2a – 2g covering a range greater than 15 pK units in DMSO. It was found that the bis(monoalkylated) product 3 arises exclusively or predominantly from the carbanions 2d – 2g derived from the less acidic carbon acids 7d – 7g whereas the cyclic product of dialkylation 4 prevails in the reaction of the carbanions 2a – 2c derived from the more acidic carbon
Nickel Catalyzed Selective Arylation of Geminal Dinitriles: Direct Access to α-Cyano Carbonyl Compounds
作者:Anwesha Bhattacharya、Subhashini V. Subramaniam、Nagesh Kumar Kandukuri、Saravanan Peruncheralathan
DOI:10.1021/acs.joc.3c02595
日期:2024.2.16
The catalytic intermolecular arylation of disubstituted geminal dinitriles with in situ generated arylnickel complexes is disclosed. This method efficiently provides various all-carbon substituted α-cyanocarbonyl compounds without additives and an inert atmosphere. It also demonstrates the arylation of R-BINOL and S-BINOL derived geminal dinitriles, preserving optical purity. Mechanistic studies proved