Hirata Yasuhiro, Inui Tomohiko, Nakao Yoshiaki, Hiyama Tamejiro
Department of Material Chemistry, Graduate School of Engineering, Kyoto University, Kyoto 615-8510, Japan.
J Am Chem Soc. 2009 May 13;131(18):6624-31. doi: 10.1021/ja9010282.
Cyanoformate esters add across 1,2-dienes in the presence of a nickel/PMe(2)Ph catalyst to afford beta-cyano-alpha-methylenealkanoates regioselectively, which are kinetically favored and readily isomerize to thermodynamically favored alpha-cyanomethyl-alpha,beta-unsaturated carboxylates at high temperature under the nickel catalysis, possibly through oxidative addition of the C-CN bond. Similar cyanoesterification products are produced from chloroformate esters, trimethylsilyl cyanide, and 1,2-dienes in the presence of a nickel/dppp catalyst. The resulting cyanoesterification products have a structure of allylic cyanide and thus undergo further allyl cyanation reaction across alkynes with the aid of a nickel/P(4-CF(3)-C(6)H(4))(3) catalyst to afford highly substituted acrylonitrile derivatives.
在镍/二苯基膦甲基苯(PMe(2)Ph)催化剂存在下,氰基甲酸酯与1,2 - 二烯加成,区域选择性地生成β - 氰基 - α - 亚甲基链烷酸酯,这些产物在动力学上有利,并且在镍催化下于高温下容易异构化为热力学上有利的α - 氰甲基 - α,β - 不饱和羧酸酯,可能是通过C - CN键的氧化加成实现的。在镍/1,3 - 双(二苯基膦基)丙烷(dppp)催化剂存在下,由氯甲酸酯、三甲基硅基氰化物和1,2 - 二烯也能生成类似的氰基酯化产物。所得的氰基酯化产物具有烯丙基氰的结构,因此在镍/三(4 - 三氟甲基苯基)膦(P(4 - CF(3) - C(6)H(4))(3))催化剂的帮助下,能与炔烃进一步发生烯丙基氰化反应,生成高度取代的丙烯腈衍生物。