Bis(triazacyclohexane) sandwich complexes of (CuI)2, CuII and ZnII: complexes with cuprophilic attraction between two cationic copper(i) leading to unusual reactivity with dioxygen

Abstract

As the first 1st-row transition metal complexes having six tertiary amine donor groups, bis(triazacyclohexane) sandwich complexes [L₂M](BF₄)₂ (L = benzyl- or p-fluorobenzyl-triazacyclohexane, M = Cu or Zn) have been obtained by the protonolysis of Et₂Zn in the presence of L or by reaction of [Cu(MeCN)₄](BF₄) with L in CH₂Cl₂ and subsequent air oxidation via an unprecedented Cu(I)₂ sandwich complex containing a short Cu–Cu contact.