Total Synthesis of (±)-Cephalosol via Silyl Enol Ether Acylation

Abstract

An efficient total synthesis of (±)-cephalosol is reported. Key steps are the acylation of a silyl enol ether with monomethyl oxalyl chloride and the subsequent acid-mediated ring closure to the isocoumarin structure. A chemoselective allylation and the conversion of the olefin into a methyl acetate were applied to install the γ-lactone moiety.

Key words

acylation - cephalosol - chemoselectivity - isocoumarins - lactones

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