Enantioselective Michael addition of malonates to α,β-unsaturated ketones catalyzed by 1,2-diphenylethanediamine†
Abstract
A general and highly enantioselective Michael addition of malonates to cinnamones and chalcones has been developed. The commercially available 1,2-diphenylethanediamine could be directly utilized as the organocatalyst to furnish the desired adducts in satisfactory yield (61–99%) and moderate to excellent enantiopurity (65 to >99% ee). β-Ketoester was also a competent donor and was employed to construct densely functionalized cyclohexenones via a tandem Michael-aldol condensation process.