Patent ID: 7119212

Claim:
A process for the preparation of 6-methyl-4-(R)-phenyl-chroman-2-one (Ia) or 6-methyl-4-(S)-phenyl-chroman-2-one (Ib), comprising the reaction of 6-methyl-coumarin (II) with a compound selected from the group consisting of formulae (III), (IV), (V), and (VI) in the presence of a chiral catalyst, in which: in the compound of formula (III), each of R 1 and R 2 is independently a hydrogen atom, a C 1 –C 6 alkyl group, an optionally substituted aryl or heteroaryl group; or R 1 and R 2 , taken together, form a C 2 –C 6 alkylene chain; or —OR 1 and —OR 2 , taken together with the boron atom they are linked to, form a group of formula in the compounds of formula (IV) and (VI) Ph is phenyl; in the compound of formula (V) M + is a metal cation selected from Li, Na, K, Rb and Cs; and in the compound of formula (VI) R is a C 1 –C 6 alkyl group.