Tin(iv) halide complexes of AsPh3: The structures of trans-SnCl4(AsPh3)2 and SnBr4(AsPh3)·AsPh3

Abstract

The structures of two 1 ∶ 2 adducts between tin(IV) halides and AsPh₃ have been determined. SnCl₄(AsPh₃)₂ adopts a six-coordinate geometry at tin in which the two organoarsine donors are mutually trans. In contrast, SnBr₄(AsPh₃)₂ is five-coordinate at tin and only one arsine is directly bonded to the metal, in an axial site of the trigonal bipyramid. The second AsPh₃ group has a close contact with the axially bound bromine [As⋯Br: 3.567(3) Å], which is a unique structural variation that depicts an intermediate in a halogen-transfer reaction between Group 14 and Group 15 elements. AACVD using SnCl₄(AsPh₃)₂ generates a film containing SnO₂ and a second crystalline material which is possibly SnCl₂, but which contains no arsenic.