Synthesis, characterization and behaviour in solution of organotin complexes based on azole ligands. Single crystal X-ray study of dichlorodimethylbis(1,2,3-benzotriazole)tin(IV)

Nine new organotin complexes, namely [SnR2XY(BtzH)2] (1: R = Me, X = Y = Cl, 2: R = Me, X = Y = Br, 3: R = nBu, X = Cl, Y = OH; 4: R = Ph, X = Y = Cl; 5a: R = Me, X = Y = NO3; 5b: R = Me, X = Y = ClO4) and [SnR2X2(5-NO2indH)2] (6: R = Me, X = Cl; 7: R = nBu, X = Cl; 8: R = Me, X = 5-NO2ind) were obtained by reaction of SnR2X2 with BtzH (1,2,3-benzotriazole) and 5-NO2indH (5-nitroindazole). These compounds were characterized by IR, NMR and ESI MS, and 1 is shown by a single crystal X-ray study to comprise mononuclear centrosymmetric molecules, all pairs of ligands being mutually opposed in a quasi-octahedral coordination sphere. Sn–Cl, C, N are 2.5700(5), 2.108(2), 2.357(2)Å. A new triclinic (image) polymorph of the binuclear [{tBu2ClSn(μ-OH)}2], 9 is also described (cf. the earlier monoclinic (P21/c)). The unit cell contents comprise a pair of centrosymmetric dimers: Sn–O are 2.042(4)–2.215(4), Sn–Cl 2.489(2), 2.491(2), Sn–C 2.166(6)–2.203(7) Å, O–Sn–O 68.4(2) (x2), and Sn–O–Sn 111.6(2)° (x2).