Patent ID: 7723531

Claim:
A process for preparing a (1R, 2S, 5S) salt of Formula IA or a (1S, 2R, 5R) salt of Formula IaA: wherein R represents an alkyl, substituted alkyl, aryl, substituted aryl, aralkyl substituted aralkyl, cycloalkyl, or substituted cycloalkyl group; “Xd” is selected from D-DTTA (di-p-toluoyl-D-tartaric acid) and D-DBTA (dibenzoyl-D-tartaric acid), and “XI” is selected from L-DTTA (di-p-toluoyl-L-tartaric acid) and L-DBTA (dibenzoyl-L-tartaric acid), said process comprising: (i) converting a compound of formula II to a compound of formula III: (ii) reducing the compound of formula III to yield a compound of formula IV: (iii) oxidizing the compound of formula IV to yield the racemic mixture comprising the imines of formulae Va and Vb: (iv) cyanating the racemic mixture of the imines of formulae Va and Vb to form a racemic mixture of trans-compounds of formula VI: (v) optionally without isolation, performing a solvolysis on the formula VI racemic mixture of compounds with ROH, where R is defined above, to form the formula VII racemic mixture of compounds: and (vi) reacting the formula VII racemic mixture of compounds with an acid selected from: (i) di-p-toluoyl-D-tartaric acid and dibenzoyl-D-tartaric acid to form the salt compound of Formula IA, and (ii) di-p-toluoyl-L-tartaric acid and dibenzoyl-L-tartaric acid salt to form the salt compound of formula IaA, wherein R, XI, and Xd are as defined above.