手性伯胺催化剂用于顺式选择性的不对称Cross-Aldol反应

摘要

基于酸碱作用,将手性伯胺与质子酸原位结合制得有机小分子催化剂,并用于醛与醛的不对称Cross-aldol反应.与一般手性仲胺催化剂不同,该类伯胺催化剂得到的是顺式选择性构型的Cross-aldol产物,其产率达90%,顺反比和ee值分别为9∶1和90%.相比而言,采用简单易得的(1S,2S)-(+)-环己二胺即可得到较高选择性的顺式产物.%Based on the "acid-base" interaction strategy, organocatalysts for the asymmetric cross-aldol reaction were synthesized by the in situ combination of chiral primary amines with protonic acids. Unlike general secondary amine catalysts that give anti-selective products,as-prepared primary amine catalysts can give syn-selective cross-aldol products with high yield and high selectivity (up to 90％ yield, 90:10 syn/anti ratio, 90％ ee). Compared with the complex synthesis of the reported catalysts, the primary amine catalyst that gave the best results was easily prepared using commercial available (1S,2S)-(+)-cyclohexanediamine.