Oxidation of rhodium(I) carbonyl chloride, [Rh(CO) 2 Cl] 2 , with copper(II) acetate or isobutyrate in methanol solutions yields binuclear double carboxylato bridged rhodium(II) complexes with Rh Rh bonds, [Rh(μ-OOCR κO)(COOMe κC)(CO)(MeOH)] 2 , where R=CH 3 or i-C 3 H 7 . According to X-ray data, surrounding of each rhodium atom in these complexes is close to octahedral and consists of another rhodium atom, two oxygens of carboxylato ligands, terminal carbonyl group, C-bonded methoxycarbonyl ligand, and axial CH 3 OH. Methoxycarbonyl ligand is shown to originate from CO group of the parent [Rh(CO) 2 Cl] 2 and OCH 3 group of solvent. N- and P-donor ligands L (p-CH 3 C 6 H 4 NH 2 , P(OPh) 3 , PPh 3 , PCy 3 ) readily replace the axial MeOH yielding [Rh(μ-OOCR κO)(COOMe κC)(CO)(L)] 2 . The X-ray data for the complex with R=i-C 3 H 7 , L=PPh 3 showed the same molecular outline as with L=MeOH. Electronic effects of axial ligands L on the spectral parameters of terminal carbonyl group are essentially the same as in the known series of rhodium(I) complexes (an increase of δ 1 3 C and a decrease of ν(CO) with strengthening of σ-donor and weakening of π-acceptor ability of L).