B/N Lewis pairs have been discovered to catalyze rapid epimerization of meso-lactide (LA) or LA diastereomers quantitatively into rac-LA. The obtained rac-LA can be kinetically polymerized into poly(L-lactide) and optically resolved D-LA, with a high stereoselectivity factor kL/kD of 53 and an ee value of 91% at 50.6% monomer conversion, by a bifunctional chiral catalyst. The epimerization and enantioselective polymerization can be coupled into a one-pot process for transforming meso-LA directly into poly(L-lactide) and D-LA.