Synfacts 2005(0): 0029-0029  
DOI: 10.1055/s-2005-865380
Synthesis of Heterocycles
© Georg Thieme Verlag Stuttgart · New York

An Efficient Synthesis of Bibutenolides from 2,3-Allenoic Acids

Contributor(s): Victor Snieckus, Justin-Alexandre Morin
S. Ma*, Z. Yu, Z. Gu
Shanghai Institute of Organic Chemistry, P. R. China
PdII-Catalyzed Oxidative Dimeric Cyclization-Coupling Reaction of 2,3-Allenoic Acids: An Efficient Synthesis Bibutenolide Derivatives
Chem. Eur. J.  2005,  11:  2351-2356  
Further Information

Publication History

Publication Date:
20 July 2005 (online)


Significance

A new catalytic system for the preparation of dibutenolides by a cyclization-coupling reaction of 2,3-allenoic acids is described. Three different catalytic systems involving Pd(II) and corresponding additives have been developed, in which the key step is the regeneration of the Pd(II) species to complete the catalytic cycle. The bicyclization reaction gives excellent yields and diastereoselectivity using optically active 2,3-allenoic acids.

Comment

Allenes possess great potential in organic synthesis as chirality transfer agents (Allenes in Organic Synthesis; H. F. Schuster, G. M. Coppola, Eds.; Wiley: New York, 1984, pp 1-8; S. Ma, Q. Yu J. Org. Chem. 2003, 68, 6149-6152). Increasing interest in this area includes the use of functionalized allenes to form a variety of cyclic compounds in Pd-catalyzed coupling reactions (S. Ma, H. Xie J. Org. Chem. 2002, 67, 6575-6578). Although naturally occurring di­butenolines are not known, butenolides are common units in many bioactive natural products, including the well know vitamin C.