Chiral phosphine-squaramides as enantioselective catalysts for the intramolecular Morita-Baylis-Hillman reaction.

ABSTRACT

Novel squaramides containing tertiary phosphine were developed as chiral bifunctional organic catalysts to promote the asymmetric intramolecular Morita-Baylis-Hillman reaction of ω-formyl-enones. The adducts were obtained in high yields with good-to-excellent enantioselectivity (up to 93% ee).