Synthesis 2004(5): 779-785  
DOI: 10.1055/s-2004-815989
SPECIALTOPIC
© Georg Thieme Verlag Stuttgart · New York

Allene: As Small in Size as Versatile in Synthesis. A General Scope of its Usefulness as a C 3 -Synthon for Carbocyclic Annulations

Asunción Barbero, Francisco J. Pulido*
Departamento de Química Orgánica, Universidad de Valladolid, Valladolid 47005, Spain
Fax: +34(983)552253; e-Mail: pulido@qo.uva.es;
Further Information

Publication History

Received 16 January 2004
Publication Date:
25 February 2004 (online)

Abstract

Allenes react with silylcuprates leading to allyl- or vinylsilanes depending on the structure of the allene and the nature of the silylcuprate. The silyl group used and temperature conditions can also influence the final outcome. Reversibility is a common trend found in these processes. In general, low order cyanosilylcuprates react with allenes, at low temperature, giving allylsilanes selectively. The intermediate allysilane-vinylcuprate can be captured with a wide variety of electrophiles affording functionalized allysilanes of great potential in organic synthesis. In particular, reaction with carbon electrophiles provides new opportunities for the carbocyclic synthesis of 5-, 6- and 7-membered rings, wherein the allenic system behaves, formally, as a nucleophilic C3-synthon of high synthetic versatility.

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Pulido, F.; Barbero, A.; Castreño, P. manuscript in preparation

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Pulido, F.; Barbero, A.; Blanco, Y. manuscript in preparation

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Pulido, F.; Barbero, A.; Blanco, Y. manuscript in preparation