Hydrolytically-sensitive hexaimino and hydrolytically-inert octaamino-cryptand hosts for dicopper

The hexa-Schiff-base cryptand N[(CH2)2NCH(C6H4-m)CHN(CH2)2]3N L1 has been found to encapsulate a pair of AgI or CuI cations without hydrolytic attack on the imine bonds; a problem which is evident when the [CuII2(OH)]3+ assembly is incorporated. The structure of the dicopper complex of a singly ring-opened ligand, derived from L1, has been determined. The octaamine cryptand L2(= L1+ 12H) more easily accommodates a [Cu2(µ-X)]3+ assembly where X = imidazolate, N3– or OH–. Collinear disposition of the bridge with the Nbr–Nbr axis is confirmed in the first case by an X-ray crystallographic structure determination of the imidazolate-bridged cryptate, and inferred for the second case by spectroscopic and magnetic data, while, for the third case, magnetic susceptibility data indicate severe bending of the Cu–O(H)–Cu assembly.