The stereoselective synthesis of unsaturated nine-membered lactones using the Malherbe–Bellus variant of the Claisen rearrangement

JK Richard

Index: Kling, Marcel R.; McNaughton-Smith, Grant A.; Taylor, Richard J. K. Journal of the Chemical Society, Chemical Communications, 1993 , # 21 p. 1593 - 1595

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Citation Number: 6

Abstract

The title reaction has been used to prepare nine-membered lactones commencing from 2- vinyltetrahydrofurans and dichloroketene; the resulting Δ5-dichlorolactones are exclusively trans but dechlorination using Bu3SnH–AlBN (azoisobutyronitrile) achieves concomitant isomerisation to give the cis-unsaturated lactones.