Patent ID: 7045625

Claim:
A process for preparing a compound of the general formula (I) wherein Ar is selected from any one of phenyl, pyridinyl, thienyl, furanyl, imidazolyl, or triazolyl, comprising the steps of; A) reacting a enantiomerically pure compound of the general formula (II) wherein R 1 and R 2 are as defined above, with N,N-bis(2-chloroethyl)-2-nitrobenzeneamide of formula (III) to give compounds of the general formula (IV) wherein R 1 and R 2 are as defined above, B) Cleaving the 2-nitrobenzenesulfonyl group of compounds of the general formula (IV) to give compounds of the general formula (V) wherein R 1 and R 2 are as defined above, and C) Alkylating a compound of general formula (V); wherein R 1 and R 2 are as defined in claim 1 , with (R)-(+)-2-methyl-2-propanesulfinamide or (S)-(−)-2-methyl-2-propanesulfinamide to give a compound of the general formula (XIII) or its enantiomer, wherein R 1 and R 2 are as defined in claim 1 , B) reducing a compound of the general formula (XIII) using a hydride donating reagent, to give a compound of the general formula (XI) wherein R 1 and R 2 are as defined in claim 1 , C)) methanolysing by acid treatment a compound of the general formula (XI) to give a compound of the general formula (II) i) a compound of the general formula Ar—CH 2 —X, wherein Ar is as defined above and X is halogen, and a suitable base, or ii) a compound of the general formula Ar—CHO, wherein Ar is as defined above, and a suitable reducing agent to give compounds of the general formula (I), as defined above.