Transition metal mediated synthesis of (±)-chuangxinmycin methyl ester

Abstract

Chromium mediated synthesis of 4-iodo-1-triisopropylsilylindole followed by 4-methoxycarbonyl-methylthiation by palladium catalysed cross coupling with methoxycarbonylmethylthio(trialkyl)-stannane and aldol condensation gave the key α-thioacrylate intermediate 5. The Z-geometry of the major isomer of 5 was determined by X-ray crystal analysis. Closure of ring C by a novel fluoride ion catalysed formation of the 2a–3 bond completed a short synthesis of (±)-chuangxinmycin methyl ester 1(R = Me).