Efficient synthesis of chiral benzofuryl β-amino alcohols via a catalytic asymmetric Henry reaction.

Chiral β-amino alcohol ligands were found effective for the copper(ii)-catalyzed asymmetric Henry reaction of benzofuran-2-carbaldehydes with nitromethane, which led to the formation of (S)-enriched benzofuryl β-nitro alcohols with satisfactory enantioselectivities (up to 98% ee). Using this catalytic protocol, bioactive (S)-benzofuryl β-amino alcohols could be conveniently prepared in short steps.