A Simple and Practical Synthetic Protocol for Acetalisation, Thioacetalisation and Transthioacetalisation of Carbonyl Compounds under Solvent-Free Conditions
作者:Abu T. Khan、Ejabul Mondal、Subrata Ghosh、Samimul Islam
DOI:10.1002/ejoc.200300685
日期:2004.5
corresponding dithioacetals under identical conditions. Some of the major advantages are mild reaction conditions, a high degree of efficiency, compatibilty with other protecting groups and the lack of solvents, particularly for thioacetalisation. In addition, no brominations occur at the double bond or α to the keto position or even in the aromatic ring under these experimental conditions. (© Wiley-VCH Verlag
在室温下,在催化量的(溴二甲基)溴化锍存在下,用醇或二醇和原甲酸三乙酯处理后,多种羰基化合物可以顺利转化为相应的缩醛。类似地,在室温下使用相同的催化剂而无需任何溶剂,各种羰基化合物可以在与硫醇或二硫醇反应时转化为相应的二硫缩醛。此外,O,O-缩醛也可以在相同条件下转化为相应的二硫缩醛。一些主要优点是温和的反应条件、高效率、与其他保护基团的相容性以及缺乏溶剂,特别是对于硫代缩醛化。此外,在这些实验条件下,在双键或酮位的 α 处甚至芳环中都不会发生溴化。(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)