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 reagents RCu(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
新型的铜试剂RCu(CN)Zn I·2 BF 3 1包含各种官能团,例如酯,氰化物,氯化物或烯酸酯,它们与β,β'-二取代的烯酮反应,以高收率提供了迈克尔加合物4-7(81- 98%)。氰基取代的1,4-加合物经历新的环化反应,从而生成非常稳定的双环二氟硼烯酸酯11a-11c,可以在温和的碱性条件下将其转化为双环二酮12。报告了11b的X射线结构。