| abstract |
The invention provides a process for the preparation of a compound of formula (I), or an acid addition or base salt thereof, wherein R is phenyl optionally substituted by 1 to 3 substituents each independently selected from halo and trifluoromethyl; R1 is C1-C6 alkyl; and 'Het' is pyrimidinyl optionally substituted by 1 to 3 substituents each independently selected from C1-C4 alkyl, C1-C4 alkoxy, halo, oxo, benzyl and benzyloxy, comprising reaction of a compound of formula (II), wherein R is as previously defined for a compound of formula (I), with a compound of formula (III), wherein R1 and 'Het' are as previously defined for a compound of the formula (I) and X is chloro, bromo or iodo, in the presence of zinc, iodine and/or a Lewis acid and an aprotic organic solvent: said process being optionally followed by conversion of the compound of the formula (I) to an acid addition or base salt thereof. |