Novel Synthetic Approach to (S)-Coriolic Acid

A new synthetic approach to (S)-coriolic acid 1 has been developed, starting from the readily available (E)-1-bromo-2-trimethylsilylethene 4 and trimethylsilylacetylene 5. A simple acylation reaction of 4, followed by a coupling reaction of the halogenoderivative intermediate with 5 in the presence of a Pd(0) catalyst affords the monosilylated ketoenyne 7. After desilylation of 7, enantioselective reduction of the carbonyl group with (S)-BINAL-H leads to the alcohol 2 (e.e.=94%). A subsequent coupling reaction and stereoselective reduction of the triple bond affords the target molecule 1.