Nickel/Lewis acid-catalyzed cyanoesterification and cyanocarbamoylation of alkynes.
Cyanoformates and cyanoformamides are found to add across alkynes by nickel/Lewis acid (LA) cooperative catalysis to give beta-cyano-substituted acrylates and acrylamides, respectively, in highly stereoselective and regioselective manners. The resulting adducts serve as versatile synthetic building blocks through chemoselective transformations of the ester, amide, and cyano groups as demonstrated by the synthesis of typical structures of beta-cyano ester, beta-amino nitrile, gamma-lactam, disubstituted maleic anhydride, and gamma-aminobutyric acid. The related reactions of cyanoformate thioester and benzoyl cyanide, on the other hand, are found to add across alkynes with decarbonylation in the presence of a palladium/LA catalyst.
Hirata
Yasuhiro
Y
Department of Material Chemistry, Graduate School of Engineering, Kyoto University, Kyoto 615-8510, Japan.
Yada
Akira
A
Morita
Eiji
E
Nakao
Yoshiaki
Y
Hiyama
Tamejiro
T
Ohashi
Masato
M
Ogoshi
Sensuke
S