Sequential Rh(I)/Pd-Catalyzed 1,4-Addition/Intramolecular Allylation: Stereocontrolled Construction of γ-Butyrolactones and Cyclopropanes
摘要:
The rhodium-catalyzed conjugate addition of functionalized vinyltin reagents to alkylidene Meldrum's acids, followed by Pd-catalyzed intramolecular allylation, is a direct entry into vinyl-substituted gamma-lactones via O-alkylation and vinylcyclopropanes via C-alkylation.
Asymmetric Addition of Alkenylstannanes to Alkylidene Meldrum’s Acids
作者:Stuart J. Mahoney、Aaron M. Dumas、Eric Fillion
DOI:10.1021/ol902216y
日期:2009.11.19
Herein, we describe enantioselective addition of alkenyltin reagents possessing a reactive and sensitive allylic functionality not readilyavailable to other classes of alkenyl metals. This method is enabled by the use of highlyelectrophilic alkylidene Meldrum’s acids as acceptors and a cationic Rh(I)−diene complex as catalyst.