Patent ID: 7579487

Claim:
A process for making a compound of formula III or Formula IIIa: a pharmaceutically acceptable salt or mixture thereof, wherein: R 3 represents (CH 2 ) n C 6-10 aryl, said aryl substituted with 2 groups of R a ; R a represents C 1-6 alkyl and halogen; Z represents S(O) 2 ; Y represents NHOH; and n is 0; said process comprising: (1) reacting a compound of formula IV: wherein R 4a represents H, C 1-4 alkyl, magnesium, lithium or sodium, with a compound of formula V: in the presence of an acid selected from the group consisting of methanesulfonic acid, pTsOH, CSA, PhSO 3 H, phosphoric acids, TFA, AcOH, H 2 SO 4 , HCl and POCl 3 ; (2) heating to a temperature of about 100° C. to about 125° C., for about one to about 30 hours, to produce a compound of formula VI: (3) asymmetrically hydrogenating a compound of formula VI in the presence of a metal catalyst and ligand to produce a compound of formula III or IIIa.