Metal coordination with an amide-functionalized axially chiral resorcinarene

Abstract

The synthesis and characterization of an amide-functionalized axially chiral resorcinarene, 14,36,56,76-tetra-2-oxo-2-(2-hydroxyethylamino)ethoxy-16,34,54,74-tetramethoxy-2,4,6,8- tetrapropylresorcin[4]arene, is reported. Metal complexation with picrate salts gave crystalline products that could be structurally characterised for calcium, lanthanum, praseodymium, and ytterbium. While the details of these structures vary, the metal–ligand interactions are remarkably consistent, with coordination polymers formed through interaction between three of the amide O atoms, each binding to a different metal atom. No other potential donor atom of the macrocycle is bound to the metal atoms, with the coordination spheres completed by solvent or picrate donor O atoms.