Highly Enantioselective Intermolecular Cyclopropanation Catalyzed by Dirhodium(II) Tetrakis[3(S)-phthalimido-2-piperidinonate]: Solvent Dependency of the Enantioselection

Article abstract of DOI:10.1055/s-1997-994

The enantioselectivity in cyclopropanations catalyzed by dirhodium(II) tetrakis[3(S)-phthalimido-2-piperidinonate] has been found to be substantially improved by employing ether as the rarely used solvent. Cyclopropanations of styrenes or 1,1-disubstituted alkenes with 2,4-dimethyl-3-pentyl diazoacetate in ether are promoted by this catalyst to afford the corresponding cyclopropane products in the highest levels of enantioselectivity (up to 98% ee) reported to date for the dirhodium(II)-catalyzed intermolecular cyclopropanation reactions.