A Novel Base-Catalyzed StereoselectiveSynthesis of Trifluoromethylated Dienedinitriles
作者:Yanchang Shen、Guoping Wang、Jiahong Ni、Jie Sun
DOI:10.1055/s-2003-40513
日期:——
The trifluoromethylated γ-cyano-β,γ-unsaturated nitrile 4 was prepared by the reaction of bromo(cyanomethyl)zinc with trifluoroacylated phosphonate 3 in 67% yield (E:Z = 60:40). The E- and Z-isomers obtained were easily separated by column chromatography. Treatment of a catalytic amount of t-BuOK (20 mol%) with a mixture of (Z)-4 and N-toluenesulfonylimines 5 gave trifluoromethylated dienedinitriles 6 in 68-83% yields.