The tricyclic polar segment of fusarisetin A, designed for preparing analogues for structure-activity relationship studies of the aliphatic segment thereof, has been constructed in an enantiocontrolled manner, featuring the Yamamoto asymmetric epoxidation of a homoallylic alcohol, C3-selective ring-opening of a 3,4-epoxy alcohol, stereocontrolled merger of a gamma-lactone with Garner's counterpart, and ruthenium catalyzed ring-closing metathesis. (C) 2015 Elsevier Ltd. All rights reserved.
Transposition des oxirannes-ethanols par l'intermediaire d'alcoxyetains
作者:J.-P. Bats、J. Moulines、P. Picard、D. Leclercq
DOI:10.1016/0040-4020(82)85161-2
日期:1982.1
Oxiraneethoxytributyltins prepared from the corresponding oxiraneethanols, on heating at ∼ 200° gave, after demetalation with isophthallic acid, 2-oxetanemethanols and/or 3-oxolanols. As appears from about thirty rearrangements the choice between oxetane and oxolane formation is dependent on: (1) the relative degree of substitution of the oxirane ring; cyclization occuring predominantly at the more