Organotin(IV) Complexes of Some 2-Pyrazoline Derivatives, Part I: R3SnCl and R2SnCl2 Complexes

Abstract

Triorganotin(lV) and diorganotin(lV) compounds react with
3-aryl-5-methyl-2-pyrazoline, 3-aryl-4,5-dimethyl-2-pyrazoline and
3-aryl-5,5-dimethyl-2-pyrazoline deivatives (L) in 1: 1 molar ratio
to give complexes of the general formula R₃SnCI.L and
R₂SnCI₂.L (R = Me, Buⁿ, Ph) respectively. The complexes obtained
have been characterised physico-chemically and spectroscopically.
As revealed from the IR and ¹H NMR spectral data, the 2-pyrazoline
derivative coordinates with tin of R₃SnCI as a monodentate ligand
via one of the active donor sites, either N₂ or OH, to give pentacoordinate
tin species, whereas it coordinates with tin of R₂SnCI₂
in a bidentate fashion via both sites  either N₂ and OH  to give six member
chelate ring with tin of hexa- coordination number. All the complexes
prepared showed no conductivity in both solvents,
acetonitrile and DMF, indicating the non-ionic species,
[R₃Sn(L)CI] and [R₂Sn(L)CI₂].