A process for the preparation of an asymmetric triorganotin halide which is represented by the general formula [III] <CHEM> wherein R represents alkyl or phenyl, R* represents cyclohexyl or neophyl, and X represents a chlorine or bromine atom, which comprises reacting in the presence or absence of an inert organic solvent an asymmetric tetraorganotin compound of the general formula [I] <CHEM> with a tin (IV) halide of the general formula [II] SnX4 [II] approximately equimolar amounts to yield the reaction in mixture including compounds of the general formula of [III] and [IV] <CHEM> and subsequently, without the isolation of the asymmetric triorganotin halide [III], reacting the reaction mixture with substantially twice the molar amount, basd on monoorganotin trihalide [IV], of an ether solution of organomagnesium halide of the general formula of [V] R*MgX [V]. n
