In an attempt to prepare potassium/sodium salts of malonato-triphenylstannate, two bis(triphenyltin) malonates were obtained instead, [(C 6 H 5 ) 3 Sn] 3 [O 2 CCH 2 CO 2 ] 1.5 (1) and {[(C 6 H 5 ) 3 SnO 2 CCH 2 CO 2 Sn(C 6 H 5 ) 3 ]H 2 O}CH 3 CH 2 OH (2). This provides an excellent example of structural diversity in triorganotin carboxylates. In both complexes, the dicarboxylate was connected to the triphenyltin groups forming a linear infinite polymeric chain. Both complexes have a trans-trigonal bipyramidal geometry with the three phenyl groups occupying the equatorial plane and two oxygens at axial positions. Both short and long tin-oxygen distances were observed in 1 and 2. In 1, all carboxylates functioned as bridging bidentate ligands, resulting in an infinite 3-D polymer network propagating along all three axes. In 2, Sn1 is bonded to a carboxylate and a water molecule (Sn1-O1 2.145(3) Å , Sn1-O3 2.341(3) Å , O1-Sn1-O3 173.97(12) ). Only one carboxylate acts as a bidentate ligand allowing the carbonyl group to be axially coordinated to the adjacent tin, Sn2. Also, Sn2 is covalently bonded to the other carboxylate group in the malonate ligand (Sn2-O4 2.163(3) Å , Sn2-O5 2.353(3) Å , O4-Sn2-O5 173.47 (12) ). There is a water molecule included in the crystal lattice hydrogen bonded to the uncoordinated carbonyl in malonate.

Novel compounds of dimethyl-and dibutyltin(IV) with O-tolyl/benzyldithiocarbonatesSn) spectroscopy. The thermal behaviour of the complex 8 has been studied by TGA/DTA analysis. The complex [(n-Bu) 2 Sn(S 2 COCH 2 C 6 H 5 ) 2 ] (8) crystallizes in the monoclinic space group C2/c, in which tin adopts a distorted octahedron or skew trapezoidal bipyramidal geometry accompanied by two n-butyl chains and the two dithiocarbonate ligands coordinated in an anisobidentate fashion. Antifungal activities against fungus Fusarium sp. of these organotin(IV) derivatives exhibited enhanced activity compared to the free ligands.