Tetrachloride transition-metal dianion-induced coordination and supramolecular self-assembly of strontium dications to cucurbit[8]uril

Abstract

In the present work, we describe a kind of novel cucurbit[8]uril-based coordination supramolecular self-assembly taking place in the presence of tetrachloride transition-metal dianions ([M_transCl₄]²⁻, M_trans = Cd, Zn, Cu, Co) in HCl solution. As reported previously, the “honeycomb effect” of the tetrachloride transition-metal dianion ([M_transCl₄]²⁻ has been observed in the coordination of strontium cations to cucurbit[8]uril molecules (Q[8]s). It seems that the [M_transCl₄]²⁻ anions form a honeycomb structure with hexagonal cells filled with Sr²⁺–Q[8] linear coordination polymers in which the Sr²⁺ cations coordinate to Q[8] molecules and form zigzag coordination polymers.