Patent ID: 8030503

Claim:
A method for preparing an aldehyde compound having the formula: wherein R 1 is selected from the group consisting of H, unsubstituted lower alkyl and substituted lower alkyl; R 2 is selected from the group consisting of unsubstituted lower alkyl and substituted lower alkyl; R 3 is selected from the group consisting of H, unsubstituted lower alkyl and substituted lower alkyl; and Pg is a hydroxy protecting group; said method comprising: (a) contacting a compound of the formula: with a reducing agent under conditions sufficient to form a reduced product having the formula (b) contacting said reduced product with a mercaptan reagent and a catalyst under conditions sufficient to form a dithioacetal compound having the formula wherein each of R 6 and R 7 is independently selected from the group consisting of C 1 -C 10 alkyl, phenyl and benzyl, or R 6 and R 7 are optionally combined to form a dithiolane or dithiane ring; (c) contacting said dithioacetal compound with a hydroxyl protecting group reagent under conditions to form a protected compound having the formula (d) converting said protected compound to said aldehyde compound.