The reactions of diorganotin oxides with o-diphenylphosphinobenzoic acid ([PPh 2( o-C 6H 4COOH)], LH) in 1:1 stoichiometry afforded tetraorganodistannoxanes [{R 2Sn(OOC-C 6H 4PPh 2)} 2O] 2 (R = Me, Et, Pr n , Bu n ). o-(Diphenylphosphino)benzoic acid complexes of palladium (II) and platinum (II) with the formulae [MCl 2(LH) 2], [MCl 2(PR 3)(LH)] (PR 3 = PEt 3, PBu 3, PMePh 2; M = Pd, Pt) have been prepared. Reactions of [{Bu 2Sn(OOC-C 6H 4PPh 2)} 2O] 2 with PtCl 2(PhCN) 2 in 1:1 and 1:2 ratio gave a complex mixture of products from which [Pt(O 2CC 6H 4PPh 2) 2] was isolated. All the complexes have been characterized by elemental analyses, IR, NMR ( 1H, 13C{ 1H}, 31P{ 1H} and 119Sn{ 1H}) and UV–Vis spectroscopy. The stereochemistry of these complexes has been deduced from spectroscopic data. The structures of [{Bu 2Sn(OOC-C 6H 4PPh 2)} 2O] 2 and [Pt(O 2CC 6H 4PPh 2) 2] have been established by X-ray crystallography.