Oligomeric phosphate clusters in macrocyclic channels

Abstract

A 36-membered macrocycle, H₃1³⁺, crystallizes with a mixture of five phosphates with valences HPO₄²⁻, H₂PO₄⁻, and H₃PO₄. The macrocycles form sandwich-like channels for clusters of six phosphates interconnected through oligomeric chains of water-linked phosphates and phosphoric acid molecules. Binding studies indicate 3 : 1 phosphate : macrocycle associations in keeping with 6 : 2 phosphate : macrocycle “sandwiches.”