Versatile ligand behaviour of di-2-pyridylketone 2-aminobenzoylhydrazone (Hdpa) towards SnPh2Cl2. Crystal structures of [SnPh2(Hdpa) Cl2] and [SnPh(dpa)Cl2]

From the reaction of di-2-pyridylketone 2-aminobenzoylhydrazone (Hdpa) with SnPh 2 Cl 2 two complexes, [SnPh 2 (Hdpa)Cl 2 ] ( 1 ) and [SnPh(dPa)Cl 2 ] ( 2 ), were isolated as yellow and red crystalline products, respectively. In compound 1 the Hdpa coordinates very weakly to tin through O (2.434(7) A), N(1) (2.695(8) A) and N(3) (2.749(9) A); on the contrary, in 2 the Hdpa is deprotonated and binds much more strongly to tin through the same atoms (2.200(16), 2.162(19) and 2.140(18) A, respectively). 119 Sn NMR data in dimethyl sulphoxide suggest that the solid state structure of 2 is retained, whereas that of 1 breaks down in solution.