Patent ID: 7232902

Claim:
A process for preparing a compound of formula (I): wherein: R a and R b together are (CH 2 ) n where n is 3 or 4, to form, with the pyrimidine ring carbon atoms to which they are attached, a fused 5- or 6-membered carbocyclic ring; R 1 is phenyl optionally susbstituted by halogen; which comprises: (a) reacting a compound of formula (II) wherein R 1 , R a and R b are as defined for formula (I), or a protected derivative thereof, with a silylating agent in an inert organic solvent, in the presence of a non-aqueous catalyst; (b) treating the product from step (a) above with (trifluoromethanesulfonyloxy)-acetic acid methyl ester in an inert organic solvent; and (c) basic hydrolysis of the methyl ester resulting from step (b).