Organooxotin carboxylates where the organic group linked to the tin is
substituted by an ester group in various positions from the metal hav
e been prepared by hydrolysis and reaction with acetic acid of the cor
responding trialkynylorganotins. It was shown that, in solution, these
compounds are hexameric with hexacoordinated tins. Strong coordinatin
g effects of bridging carboxylato ligands prevent the ester groups to
coordinate to the tin atoms.