Structures and C–H⋯π interactions in DMF inclusion complexes of homoazacalix[4]arenes

The molecular packing modes of DMF inclusion complexes of three homoazacalix[4]arenes were significantly changed by altering the substituents on the azacalixarene skeleton. As for N-methyl-p-tert-butyl-homoazacalix[4]arene, one of the phenolic OH protons transferred to the nitrogen atom was being accompanied by the inclusion of a DMF molecule. The DMF molecule in the cavity of each azacalixarenes is stabilized by C–H⋯π interaction.