An efficient asymmetricsynthesis of isochromanone derivatives was realized through Z-selective-1,3-OH insertion/aldol cyclization reaction involving acyclic carboxylic oxonium ylides. The combination of achiral dirhodium salts and chiral N,N′-dioxide–metal complexes, along with the use of α-diazoketones instead of α-diazoesters, enables the cascade reaction efficiently. A variety of benzo-fused δ-lactones
Pd/C-catalyzed dehydrogenation of 2-cinnamoylbenzoic acids to 3-benzylidene-3<i>H</i>-isochroman-1,4-diones
作者:Dejun Yang、Xuan Ji、Jie Zhang、Chenyang Zhang、Mingfei Li、Jin Li、Renhua Liu
DOI:10.1039/c8cc03402h
日期:——
Pd/C, a widely accepted hydrogenation catalyst, is found to catalytically dehydrogenate 2-cinnamoylbenzoic acids to 3-benzylidene-3-H-isochroman-1,4-diones with H2 as the only byproduct.