Synthesis and crystal structures of p-tert-butylcalix[4]arene 1,3-distal acylhydrazones and macrocyclic nickel complex

Abstract

A series of the calix[4]arene 1,3-distal diacylhydrazones were successfully prepared by the condensation of calix[4]arene propylene and butylene bridged vanillines with 2-hydroxybenzohydrazide or pyridinecarbohydrazides. The coordination chemistry of these calixarene diacylhydrazone with transition metal salts was studied. X-ray single crystal diffraction of nickel complex shows that a very large metallic macrocycle with 2:2 stoichiometric is formed by two calixarene acylhydrazone domains act as bidentated planar chelators to coordinate to two nickel ion in a approximately square-planar geometry.