Novel synthetic approach to (S)-coriolic acid

A new synthetic approach to (S)-coriolic acid 1 has been developed, startin g from the readily available (E)-1-bromo-2-trimethylsilylethene 4 and trime thylsilylacetylene 5. A simple acylation reaction of 4, followed by a coupl ing reaction of the halogenoderivative intermediate with 5 in the presence of a Pd(0) catalyst affords the monosilylated ketoenyne 7. After desilylati on of 7, enantioselective reduction of the carbonyl group with (S)-BINAL-H leads to the alcohol 2 (e.c.=94%). A subsequent coupling reaction and stere oselective reduction of the triple bond affords the target molecule 1. (C) 1999 Elsevier Science Ltd. All rights reserved.