Patent ID: 7511139

Claim:
A process for the preparation of a compound of formula I, comprising: (a) converting the compound of formula 3a to a compound of formula 3b via protodesilylation, wherein R a is allyl, phenyl, or phenyl substituted with one, two or three C 1 -C 4 alkyl or C 1 -C 4 alkoxy; each R b is independently C 1 -C 4 alkyl; and R c is H or Bn, (b) further converting the compound of formula 3b to a compound of formula 3f, wherein each R b and R c are defined as hereinabove; (c) oxidizing the compound of formula 3f to give the compound of formula I when R c is H; or a compound of formula 3 g when R c is Bn, (d) deprotecting the benzyl group in the compound of formula 3g wherein R c is Bn to give a compound of I.