Synthesis of hydroxylated azacalix[1]arene[3]pyridines from hydrolysis of high valent arylcopper complexes and conversion to a double azacalix[1]arene[3]pyridine host molecule

Abstract

Hydrolysis of shelf-stable and structurally well-defined arylcopper(II) and arylcopper(III) complexes was investigated. Under alkali conditions all arylcopper(II) compounds underwent efficient hydrolysis at ambient temperature to produce exclusively lower-rim-hydroxylated azacalix[1]arene[3]pyridines in excellent yields. The identical products were obtained in only moderate yields from the same hydrolytic reaction of arylcopper(III) compounds. The latter reaction also yielded a 4,4′-biphenol-joint double azacalix[1]arene[3]pyridine product. The double azacalix[1]phenol[3]pyridine was then prepared in good yield from the CuCl₂/TMEDA-catalyzed oxidative homocoupling of two azacalix[1]phenol[3]pyridines. The supramolecular application of the resulting double azacalixaromatics was demonstrated by their complexation with aliphatic diamines to form one-dimensional molecular assemblies in the solid state.