Synthesis 2007(4): 597-607  
DOI: 10.1055/s-2007-965890
PAPER
© Georg Thieme Verlag Stuttgart · New York

Regioselective Synthesis of (E)-5-(Tributylstannylmethylidene)-5H-furan-2-ones and (E)-3-(Tributylstannylmethylidene)-3H-isobenzofuran-1-ones: Easy Access to γ-Alkylidenebutenolide and Phthalide Skeletons

Alain Duchênea, Jérôme Thibonneta, Jean-Luc Parrainb, Elsa Anselmia, Mohamed Abarbri*a
a Laboratoire de Synthèse et Physicochimie Organique et Thérapeutique, EA 3857, Faculté des Sciences de Tours, Parc de Grandmont, 37200 Tours, France
Fax: +33(2)47367073; e-Mail: mohamed.abarbri@univ-tours.fr;
b Laboratoire Symbio, Equipe Synthèse par Voie Organométallique, associé au CNRS (UMR 6178, Université Paul Cézanne, Aix Marseille III, Campus scientifique de Saint Jérôme, Avenue Escadrille Normandie-Niemen, 13397 Marseille Cedex 20, France
Further Information

Publication History

Received 24 October 2006
Publication Date:
12 January 2007 (online)

Abstract

Regio- and stereoselective synthesis of γ-alkylidene­butenolides and γ-alkylidenephthalides has been achieved through the palladium-catalysed tandem cross-coupling/cyclisation reactions of tributylstannyl-3-iodopropenoate or the 2-iodo benzoate derivatives with tributyltinacetylene. Iododestannylation occurred with inversion of the configuration of the exocyclic double bond in the case of butenolides, but with retention of configuration for the phthalide. The selectivity observed in the Stille reaction was found to be dependent on the nature of the vinyl or the aryl halide.

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AM1 calculations were performed by the Hyperchem pack-age on a PC computer. (Z)-4c: E = -2418.816 kcal×mol-1. (E)-4c: E = -2416.067 kcal×mol-1 (r.m.s. energy gradient <0.001).