Preparation of enantiopure 3,5,5-trialkyl-γ-butyrolactones by diastereospecific 5-endo halo lactonizations
作者:Jean-Marc Garnier、Sylvie Robin、Régis Guillot、Gérard Rousseau
DOI:10.1016/j.tetasy.2007.05.028
日期:2007.7
A new preparation of 3,5,5-trialkyl-gamma-butyrolactones of defined absolute configuration is reported. This method involves the diastereoselective alkylation of 3,4-ethylenic acids after incorporation of a chiral Evans auxiliary, and then after separation of the two diastereomers and hydrolysis of the auxiliary, stereospecific halo lactonizations. This method was applied to the preparation of a natural product, present in a sponge. (c) 2007 Elsevier Ltd. All rights reserved.