Tetrahedron letters

General facile synthesis of 2, 5-diarylheteropentalenes

P Vachal, LM Toth

Index: Vachal, Petr; Toth, Leslie M. Tetrahedron Letters, 2004 , vol. 45, # 38 p. 7157 - 7161

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Citation Number: 58

Abstract

Palladium-catalyzed cross-coupling reactions of various heteropentalene derivatives were systematically studied. A general three-step synthesis of 2, 5-diarylheteropentalenes involving two Suzuki or Negishi couplings and a regiospecific bromination was developed. Nonsymmetrical 2, 5-diaryl-furans, thiophenes, pyrroles, 1, 3-thiazoles, 1, 3-oxazoles, 1, 3, 4- thiadiazoles, and 1, 3, 4-oxadiazoles were prepared in 31–67% isolated yield (three steps ...