The reaction of tin(iv) iodide with phosphines: formation of new halotin anions

Abstract

The reaction of SnI₄ with each of a primary, secondary and tertiary phosphine has been investigated and in none of the cases are simple adducts formed. With Cy₃P, [Cy₃PI]⁺ salts of both [SnI₃]⁻ (1) and [SnI₅]⁻ (2) are isolated arising from reactions involving both reduction at tin and halogen transfer. With the secondary and primary amines Ph₂PH and CyPH₂, respectively, additional HI elimination reactions occur and the salts [Ph₂PH₂]⁺₆[Sn₃I₁₂]⁶⁻ (3), [Ph₂PH₂]⁺₂[SnI₆]²⁻ (4) and [CyPH₃]⁺₂[SnI₄]²⁻ (5) have been isolated_. Compounds 1–5 have been characterised crystallographically.