Decarboxylation of metal carboxylates provides a route to numerous main group element organometallics(1, 2), and to several transition metal organometaliics in which the central metal has a closed shell (d10) configuration(1, 2), e.g. organocopper(I) derivatives(3-5). Extensions to compounds with non-d10 central metals are restricted to some organonickel(II) derivatives(6). In addition, π-allylplatinum(II) complexes have been prepared by decarboxylation of allyloxycarbonyl-and N-allylcarbamoylplatinum(II) compounds(7), but the reactants are not carboxylato complexes since the -C(O)O-groups are carbon-bonded to platinum. We now report decarboxylation syntheses of some organorhodium(I) and organoplatinum(II) compounds from suitable metal carboxylates. Reaction of trans-RhCl(CO)(Ph3P)2 with some thallous polyfluorobenzoates, TlO2CR, in pyridine at room temperature (R = C6F5) or on heating (R = C6F5, p-HC6F4 or m-HC6F4) resulted in decarboxylation and formation of the corresponding organorhodium compound (Table).