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Published on: November 9, 2019
Synthesis of polyketide stereoarrays enabled by a traceless oxonia-Cope rearrangement
Lin Yang1, Guoli He, Ruifeng Yin
1CAS Key Laboratory of Synthetic Chemistry of Natural Substances, Shanghai Institute of Organic Chemistry, CAS, 345 Lingling Road, Shanghai 200032 (China) http://honggroup.sioc.ac.cn.
Abstract:
Polyketide antibiotics bearing skipped polyols represent a synthetic challenge. A SiCl4-promoted oxonia-Cope rearrangement of syn,syn-2-vinyl-1,3-diols was developed to forge an array of 1,5-pentenediols, thus providing versatile motifs for the preparation of 1,2,3,5-stereoarrays in a highly stereoselective manner. Further exploration with Sn(OTf)2 realized the rearrangement of a cross-aldehyde which tactically warrants the utility of the current approach to access complex polyketides. The origin of high stereoselectivity is attributed to a chairlike anti-conformation of the oxonium ion intermediate.
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