Reaction of tin(IV) and tin(II) halides with transition-metal ion Schiff-base complexes

Abstract

The planar transition metal compounds NN′-ethylenebis(salicylideneaminato)metal(II)[M^II(salen)] where the metal ion is cobalt(II), nickel(II), or copper(II), react with the halides SnX₄ and SnX₂(where X = Cl or Br) to form 1 : 1 adducts. Characterisation of these adducts using magnetic data, and diffuse reflectance and i.r. spectroscopy indicates a retention of planarity about the transition-metal ion. Structures are suggested for the adducts. A mechanism is put forward to explain the metal-exchange reaction observed in polar solvents for the adducts Co^II(salen)SnX₄, leading to the compounds SnX₂(salen).