Patent ID: 8309715

Claim:
A method of asymmetric addition of organozinc to an aldehyde, to form at least one of comprising a step of reacting R 3 C(O)H with R 4 ZnR 5 in the presence of a catalyst of the following formula (Ib), wherein each of R 1 and R 2 , independently, is alkyl having two or more carbon atoms, or R 1 and R 2 taken together is (CH 2 ) m X(CH 2 ) n ; each of R 3 , R 4 and R 5 , independently, is alkyl, alkenyl, cycloalkyl, cycloalkenyl, heterocycloalkyl, heterocycloalkenyl, aryl, or heteroaryl; X is O, S, or CH 2 ; and each of m and n, independently, is 1, 2 or 3, and the sum of m and n is 3 or 4.