New S,O-acetals from (1R)-(−)-myrtenal as chiral auxiliaries in nucleophilic additions
作者:Luis Chacón-Garcı́a、Selene Lagunas-Rivera、Salvador Pérez-Estrada、M. Elena Vargas-Dı́az、Pedro Joseph-Nathan、Joaquı́n Tamariz、L.Gerardo Zepeda
DOI:10.1016/j.tetlet.2004.01.046
日期:2004.3
Treatment of hydroxythiol 4 with alpha,alpha-diethoxyacetophenone at room temperature yielded a mixture of epimeric S,O-acetals 6 and 7 (1:4. 92%, yield), which were efficiently separated by flash chromatography. The OTBS derivatives 8 and 9 were treated with several Grignard reagents to afford carbinols 10 and 13 respectively (85-99%, yield, >95% dr). After successive hydrolysis and reduction of 10 and 13 it is possible to obtain either enantiomer of diols 16 in high optical purity (>95% er). (C) 2004 Elsevier Ltd. All rights reserved.