Patent ID: 8410312

Claim:
A process for preparation of a compound of formula (I): wherein phenyl ring A is optionally substituted by 1 to 4 substituents; R 1 is C 1-6 alkyl, C 2-6 alkenyl, or C 2-6 alkynyl; which comprises: (i) reaction of a corresponding compound of formula (II): wherein ring A is optionally substituted as defined for the compound of formula (I); R 2 is hydrogen, C 1-10 alkyl, C 1-10 haloalkyl, C 6-14 aryl, C 6-14 arylalkyl, or —(CH 2 CH 2 O) q —CH 3 wherein q is an integer of from 1 to 10; R 1 is as defined for the compound of formula (I); and R 3 is a leaving group; with fluoride or an isotope thereof to give a compound of formula (III), whereby said leaving group is displaced by said reaction with fluoride or an isotope thereof wherein R 1 and R 2 are as defined for the compound of formula (I) and phenyl ring A is substituted as defined for the compound of formula (I); followed by step (ii) and optionally step (iii) in any order (ii) conversion of group —C(O)R 2 to hydrogen, (iii) removal of any protecting groups.