A New Mild Deprotecting Method for<i>O</i>-Benzylsulfonyl Phenols and Alcohols Based on a DTBB-Catalyzed Lithiation
作者:Gabriel Radivoy、Miguel Yus、Francisco Alonso、Yanina Moglie、Cristian Vitale
DOI:10.1055/s-2005-869907
日期:——
A variety of alcohols and phenols, protected as the corresponding benzylsulfonic esters, were efficiently deprotected by selective reductive cleavage of the sulfur-oxygen bond, using an excess of lithium sand and a catalytic amount (5 mol%) of 4,4′-di-tert-butylbiphenyl (DTBB) as electron carrier, in THF at 0° C. This deprotection system was also efficient at -50 °C and was compatible with a wide range of other functional groups.
多种醇和酚的保护形式,即相应的苄磺酸酯,通过选择性还原切割硫-氧键得以高效去保护。该过程使用过量锂粉和催化量的(5摩尔%)4,4'-二叔丁基联苯(DTBB)作为电子载体,在THF中于0°C进行。这种去保护系统在-50°C下同样高效,并且与多种其他官能团相容。