摘要:
Some organotin(IV) triazolates of general formula RnSn(L)(4-n) (where R = Me, n-Bu and Ph for n = 2; R = Me, n-Pr and n-Bu for n = 3 and HL = 3-amino-5-mercapto-1,2,4-triazole) have been synthesized by the reaction of R2SnCl2/R3SnCl with NaL in 1:2/1:1 molar ratio. Whereas, Oct(2)SnL(2) has been synthesized azeotropically by the reaction of Oct(2)SnO and HL in 1:2 molar ratio. As good single crystals were not obtained, a large number of experimental techniques, viz. U-V/Vis, IR, far-IR, multinuclear (H-1, C-13 and Sn-119) NMR and Sn-119 Mossbauer spectroscopic studies, were used to accomplish a definitive characterization and determination of their most probable structures. In these compounds triazole acts as a monoanionic bidentate ligand, coordinating through S-exo and N(4). The IR and Sn-119 Mossbauer spectroscopic studies allow us to deduce a highly distorted cis-trigonal-bipyramidal structure for R3SnL and a distorted skew trapezoidal-bipyramidal structure for R2SnL2, in the solid state. However, H-1, C-13 and Sn-119 NMR spectral studies revealed that weak bonding between tin and N(4) is further weakened in the solution leading to pseudo-tetrahedral/tetrahedral structure. (c) 2005 Elsevier B.V. All rights reserved.