1,4-Additions of the highly functionalized copper reagents RCu(CN)ZnI · 2 BFP3 to trisubstituted enones. A new BF3 promoted cyclization reaction
作者:Ming Chang P. Yeh、Paul Knochel、William M. Butler、Scott C. Berk
DOI:10.1016/s0040-4039(00)82430-2
日期:——
The new copper reagentsRCu(CN)Zn I · 2 BF31 containing various functional groups like esters, cyanides, chlorides or enoates react with β, β′- disubstituted enones to afford the Michael adducts 4–7 in high yields (81–98%). Cyano-substituted 1,4-adducts undergo a new cyclization reaction leading to the very stable bicyclic difluoroboron enolates 11a–11c which could be converted into the bicyclic diketones