Facile approach towards the synthesis of homochiral functionalised alcohols from 4-O-[(tert)-butyldimethylsilyl]-2,3-O-cyclohexylidene-L-threose of (L)-(+)-tartaric acid origin

摘要

(L)-(+)-Diethyl tartarate 2 has been transformed into the aldehyde 6. Grignard additions to 6 take place with moderate diastereoselectivity giving predominant formation of the anti products 8a-e. However, in each case the diastereoalcohols are easily separable by column chromatography giving rise to the formation of a series of functionalised homochiral alcohols 7 and 8. On the other hand Zn mediated allylation and propargylation of 6 in the presence of water proceeded efficiently with almost absolute (>99%) stereoselective formation of versatile functionalised homoallylic 8d and homopropargylic 8e alcohols respectively. (C) 1998 Elsevier Science Ltd. All rights reserved. [References: 46]