Telluroether adducts of tin(IV) halides: synthesis, spectroscopy and structures

Abstract

The extremely moisture-sensitive [SnX₄(Me₂Te)₂] and [SnX₄(ditelluroether)] [X = Cl or Br; ditelluroether = C₆H₄(TeMe)₂-o, MeTe(CH₂)₃TeMe or PhTe(CH₂)₃TePh] have been prepared from SnX₄ and the tellurium compound in anhydrous dichloromethane. The crystal structures of [SnCl₄{C₆H₄(TeMe)₂-o}] and [SnBr₄{C₆H₄(TeMe)₂-o}] have been determined; both show distorted-octahedral tin(IV) with the chelating ditelluroether ligand adopting the meso conformation. Variable-temperature ¹H, ¹²⁵Te-{¹H} and ¹¹⁹Sn-{¹H} NMR studies showed that the complexes undergo rapid ligand exchange in solution. The structures and properties are compared with those of previously described thio- and seleno-ether analogues. Multinuclear NMR spectroscopic studies of mixtures of SiCl₄ or GeCl₄ and various Group 16 donor ligands in CH₂Cl₂ solution provided no evidence of adduct formation.