Syntheses and Crystal Structures of Two Diethyltin Complexes of N-Salicylidene-α-amino Acid

摘要

Two novel diethyltin(IV) complexes of N-salicylidenevaline(H2L1) and N-Sali-cylidenetryptophan(H2L2), Et2SnL1 1 and Et2SnL2 2, were synthesized and characterized by elemental analysis, IR, 1H NMR and X-ray single-crystal diffraction analysis.Complex 1 belongs to the trigonal system, space group R-3 with a = b = 19.2730(5), c = 23.6890(13) , V = 7620.4(5) 3, Z = 6, Dc = 1.553 g/cm3, μ = 1.518 mm-1, F(000) = 3600, R = 0.0238 and wR = 0.0636.Complex 2 is of monoclinic system, space group P21/c with a = 13.7550(8), b = 11.5425(7), c = 12.7876(7) , β = 93.585(1)°, V = 2026.3(2) 3, Z = 4, Dc = 1.548 g/cm3, μ = 1.286 mm-1, F(000) = 976, R = 0.0298 and wR = 0.0722.Complex 1 is a cyclic trimer with a macrocyclic 12-membered ring structure formed by the bidentate bridging coordination of carboxylate group to tin atoms.The tin atom is six-coordinated in a distorted octahedral geometry.In complex 2, the distorted trigonal bipyramidal Et2SnL2 units are linked into polymeric chains by the weak Sn…O interaction involving Sn and the carbonyl O of an adjacent ligand, and the chains are further connected by intermolecular N-H…O hydrogen bonds to form a two-dimensional supramolecular structure.