Biocidal organotin compounds .2. Synthesis, characterization and biocidal properties of triorganotin(IV) hydantoic acid derivatives and the crystal structures of triphenyltin and tricyclohexyltin hydantoates

The preparation and spectroscopic (H-1 NMR, UV and IR) characterization of three R(3)Sn(O2CCH2N(H)C(O)NH2) [R = Ph, c-Hex (cyclohexyl) or n-Bu] compounds are reported, A different mode of coordination is indicated for the hydantoate ligand in the R = Ph compound compared with the R = c-Hex and R = n-Bu compounds, as confirmed by a crystallographic analysis, The structure of [Ph(3)Sn(O2CCH2N(H)C(O)NH2)] is polymeric owing to the presence of bridging hydantoate ligands such that each ligand coordinates one tin atom, via one of the carboxylate oxygen atoms, and a symmetry-related tin atom via the carbonyl group at the other end of the molecule, The structure features distorted trigonal-bipyramidal tin atom geometries with a trans-R(3)SnO(2) motif, The structure of [c-Hex(3)Sn(O2CCH2N(H)C(O)NH2)], by contrast, is monomeric, distorted tetrahedral, as the carboxylate group is monodentate and there are no additional tin-ligand interactions, The structures are each stabilized by a number of intermolecular hydrogen bonds, Fungitoxicity and phytotoxicity studies indicate that the R = n-Bu derivative is the more active compound.