Tetrahedron

Studies towards the synthesis of obtusenyne. A Claisen rearrangement approach to unsaturated nine-membered lactones.

NR Curtis, AB Holmes, MG Looney

Index: Curtis, Neil R.; Holmes, Andrew B.; Looney, Mark G. Tetrahedron, 1991 , vol. 47, # 34 p. 7171 - 7178

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Citation Number: 36

Abstract

An advanced intermediate for the synthesis of the Laurencia oxonane natural product obtusenyne 1. namely the unsaturated nine-membered lactone 3, was efficiently prepared in seven steps from (E)-3-hexenoic acid 7. The key transformation was the Claisen rearrangement of the vinyl ketene acetal 4, which represents novel methodology for the preparation of such unsaturated nine-membered lactones.