A macrobicyclic AgI3 cage encapsulating two cobalt(III) ions: synthesis, structure and reactivity

Abstract

Reaction of the S-bridged Co^III₂Ag^I₃ pentanuclear complex, [Ag^I₃{Co^III(aet)₃}₂]³⁺ (1; aet = NH₂CH₂CH₂S^–), with para-formaldehyde in basic acetonitrile, followed by adding aqueous ammonia, produces the aza-capped complex, [Ag^I₃-{Co^III(L)}₂]³⁺ [2; L = N(CH₂NHCH₂CH₂S^–)₃] , in which two Co^III atoms are encapsulated in a macrobicyclic cage consisting of two aza-capped ligands L and three Ag^I atoms; 2 is converted to the aza-capped Co^III₄Zn^II₄ octanuclear complex, [Zn^II₄O{Co^III(L)}₄]⁶⁺, by the reaction with I^– in the presence of ZnO and Zn²⁺ in water, retaining the chiral configuration of the aza-capped [Co^III(L)] units.