Process for preparing amine platinum complexes

The present invention relates to the area of platinum drugs. In particular, it relates to an improved process for preparing platinum complexes having the general formula (Ia) or (Ib): as defined of herein,comprising:1a) a first step, wherein [PtA4]2- is reacted with L under appropriate conditions in a first solvent to form [PtA3(L)]-;1b) a second step, wherein [PtA3(L)]- is reacted with L' under appropriate conditions in a second solvent to form cis-[PtA2(L')(L)];1c) in the case where Y is halogen or hydroxy a third step, wherein cis-[PtA2(L')(L)] is reacted with H2O2, Y2 or halogen containing oxidant to form c,t,c-[PtA2Y2(L')(L)]; in the case where Y is carboxylate, carbamate or carbonate ester a fourth step, wherein an intermediate, where Y is hydroxy formed in step 1c), is functionalized with an appropriate acylating agent; and1d) in the case where A is not a halide or is different from the original halide, additional step(s) in which the original halide A of an intermediate formed in step 1a or 1b 1c or 1d is converted to a different halide or a new leaving group(s) A such as mono-dentate hydroxy, alkoxy, carboxylate or bi-dentate carboxylate, phosphonocarboxylate, diphosphonate, or sulphate.