Hydroheteroarylation of alkynes under mild nickel catalysis.
Nickel complexes having a bulky tri(sec-alkyl)phosphine ligand catalyze hydroheteroarylation of alkynes at 35 degrees C. Selective activation of an Ar-H bond over an Ar-CN bond of N-protected 3-cyanoindoles is achieved by a proper choice of ligand and/or an N-protecting group. The catalysis is applicable to a diverse range of heteroarenes to afford cis-hydroheteroarylation products in highly chemo- and stereoselective manners. Excellent regioselectivity is observed with unsymmetrical alkynes to give the corresponding heteroaryl-substituted ethenes having a larger substituent trans to an aryl group.
Nakao
Yoshiaki
Y
Department of Material Chemistry, Graduate School of Engineering, Kyoto University, Kyoto 615-8510, Japan. nakao@npc05.kuic.kyoto-u.ac.jp
Kanyiva
Kyalo Stephen
KS
Oda
Shinichi
S
Hiyama
Tamejiro
T