Cyanoesterification of 1,2-dienes catalyzed by nickel.
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.
Hirata
Yasuhiro
Y
Department of Material Chemistry, Graduate School of Engineering, Kyoto University, Kyoto 615-8510, Japan.
Inui
Tomohiko
T
Nakao
Yoshiaki
Y
Hiyama
Tamejiro
T