Rhenium(VII) Catalysis of Prins Cyclization Reactions
作者:Kwanruthai Tadpetch、Scott D. Rychnovsky
DOI:10.1021/ol8019204
日期:2008.11.6
The rhenium(VII) complex O3ReOSiPh3 is a particularly effective catalyst for Prinscyclizations using aromatic and alpha,beta-unsaturated aldehydes. The reaction conditions are mild, and the highly substituted 4-hydroxytetrahydropyran products are formed stereoselectively. Rhenium(VII) complexes appear to spontaneously form esters with alcohols and to directly activate electron-rich alcohols for solvolysis
VII络合物O3ReOSiPh3是使用芳香族和α,β-不饱和醛对Prins环化反应特别有效的催化剂。反应条件温和,且立体选择性地形成高度取代的4-羟基四氢吡喃产物。hen(VII)络合物似乎能与醇自发形成酯,并直接活化富电子的醇进行溶剂分解。Re 2 O 7和高r酸在催化这些环化方面同样有效。