Synthesis of 5-alkylidene-2,5-dihydropyrrol-2-ones based on cyclizations of 1,3-bis(trimethylsilyloxy)-1,3-butadienes with oxalyl chloride
作者:Christian Haase、Peter Langer
DOI:10.1016/j.tet.2009.03.102
日期:2009.6
The acid-mediated reaction of amines with γ-alkylidenebutenolides, readily available by cyclization of 1,3-bis(silyloxy)-1,3-butadienes with oxalylchloride, allows a convenient synthesis of a variety of 5-alkylidene-2,5-dihydropyrrol-2-ones. The configuration of the exocyclic double bond of the products depends on the substitution pattern of the products.
Suzuki Cross-Coupling Reactions of γ-Alkylidenebutenolides: Application to the Synthesis of Vulpinic Acid
作者:Zafar Ahmed、Peter Langer
DOI:10.1021/jo049780a
日期:2004.5.1
α-Hydroxy-γ-alkylidenebutenolides were efficiently functionalized by Suzuki cross-coupling reactions via the corresponding enol triflates. The natural product vulpinicacid was prepared by this methodology.
The cyclization of 1,3-bis(trimethylsilyloxy)-1,3-butadienes with oxalyl chloride afforded functionalized gamma-alkylidene-alpha-hydroxybutenolides, which were transformed into cis-configured gamma-lactones by diastereoselective hydrogenation.((C) Wiley-VCH Verlag GmbH, 69451 Weinheim, Germany, 2002).