Anion-controlled assemble of C–H⋯X hydrogen bonded helical tubes or catemers by crescent imidazolium salts

Abstract

A series of 1-acetamido-3-(2-pyrimidyl)-imidazolium salts with different anions (Br− (1), NO3− (2), PF6− (3) and BF4− (4)) have been synthesized and characterized using single crystal X-ray diffraction. The crescent imidazolium moieties provide rich C–H donors and serve as building blocks to either convergently form helical tubes with Br− and NO3−, or divergently form 1-D catemers with PF6− and BF4− anions.