Highly Enantioselective Catalytic Kinetic Resolution of α-Branched Aldehydes through Formal Cycloaddition with Homophthalic Anhydrides.

A new catalytic methodology was developed to promote an efficient one-pot kinetic resolution of racemic aldehydes with selectivity (s*) of up to 91 (99:1 d.r., >99 % ee) in a cycloaddition reaction with enolizable anhydrides to afford dihydroisocoumarin products (a core prevalent in natural products and molecules of medicinal interest) containing three contiguous stereocentres.