Catalytic asymmetric three-component Mannich-type reaction of alkenyl trichloroacetates.

A catalytic enantioselective three-component Mannich-type reaction of alkenyl trichloroacetates, ethyl glyoxalate, and aniline derivatives was achieved using an (S)-BINOL-derived chiral tin dibromide possessing a 4-trifluoromethylphenyl group at the 3- and 3'-positions as the chiral precatalyst in the presence of sodium ethoxide, sodium iodide, and ethanol. Optically active beta-amino ketones with up to 98% ee were syn-selectively obtained in high yields even from imines possessing a polar amino group under the influence of the in situ generated chiral tin bromide ethoxide.