Template synthesis of polyiodide belt at a metal complex cation: structure of [([16]aneS4)M–I–M([16]aneS4)]3+[I5–]2i–(M = Pd, Pt) incorporating a symmetric linear M–I–M bridge ([16]aneS4= 1,5,9,13-tetrathiacyclohexadecane)

Abstract

Reaction of [M([16]aneS₄)][PF₆]₂ with NBuⁿ₄I₃ affords the binucleas species [([16]aneS₄)M–I–M([16]aneS₄)]³⁺(M = Pd, Pt) incorporating a highly unusual linear M–I–M moiety within a conformationally constrained environment: the counter anion, which can be regarded formally as two I₅^– and One I^– or alternatively as two I₃^–, two I₂ and one I^–, forms a belt around the complex cation with the metal-bridging I^– placed at its centre.