Three new organotin complexes (two selenito and an oxalate one) adducts have been synthesized and studied by infrared and Mössbauer techniques. A discrete structure is suggested with a bi-unidentate selenito oxyanion and trans bipyramidal SnPh3 residue; the oxalato adduct can be seen as an insertion compound between C2O4(SnPh3)2 and [Cu(En)3]C2O4•4SnPh2C2O4. This last compound has a discrete ionic structure with cis coordinated SnPh2 residues.
