The transformation of acetonides into the corresponding diacetates is often required in the synthetic chemistry. An efficient procedure for direct conversion of acetonides into diacetates in the presence of Bi(OTf)3·xH2O under mild conditions has been developed. Primary hydroxyl-acetonides could be selectively transformed into diacetates in the presence of anomeric acetonides and the anomeric acetonides
在合成化学中通常需要将丙酮化物转化为相应的二乙酸盐。开发了一种在温和的条件下在Bi(OTf)3 · x H 2 O存在下将丙酮化物直接转化为二乙酸盐的有效方法。可以在异头丙酮化物的存在下将伯羟基丙酮化物选择性地转化为二乙酸盐,并且异头丙酮化物可以可调谐地转化为2-乙酰氧基异丙基或二乙酸盐基团。
Tandem Acetalation−Acetylation of Sugars and Related Derivatives with Enolacetates under Solvent-Free Conditions
作者:Debaraj Mukherjee、Bhahwal Ali Shah、Pankaj Gupta、Subhash Chandra Taneja
DOI:10.1021/jo070363i
日期:2007.11.1
[GRAPHICS]Molecular iodine catalyzes acetalation and acetylation of reducing sugars and sugar glycosides with stoichiometric amounts of enol acetates under solvent-free conditions, thereby facilitating the synthesis of various types of orthogonally protected sugar derivatives in short time and good yields. The outcome of the reaction can be controlled by variation in temperature. Thus at lower temperature, it is possible to obtain the acetonide acetate as a single product whereas peracetate is the major product at higher temperature.