Synthesis of Vinyl-Functionalized Oxazoles by Olefin Cross-Metathesis
作者:Thomas J. Hoffman、James H. Rigby、Stellios Arseniyadis、Janine Cossy
DOI:10.1021/jo702305g
日期:2008.3.1
A ruthenium-based catalyzed olefin cross-methathesis reaction involving 2- and 4-vinyl-functionalized oxazoles was developed. A wide range of olefinic partners was coupled in good to excellent yields and high stereoselectivities under mild conditions. This methodology offers new opportunities for the synthesis of a plethora of biologically active natural products.
The ethyl oxazole-4-carboxylate was directly and regioselectively alkenylated, benzylated and alkylated with alkenyl-, benzyl-, allyl- and alkylhalides in the presence of catalytic amounts of palladiumacetate with caesium carbonate using Buchwald's JohnPhos ligand.