The synthesis and topochemical polymerization of o-carborane-based diacetylene macrocycles

Abstract

A kind of o-carborane-based macrocycle was synthesized via oxidative coupling of acetylene-terminated o-carborane precursors. Single crystal X-ray diffraction analysis unambiguously revealed their unique porous supramolecular structures, which displayed micropore characteristics. Interestingly, the crystal structure of macrocyclic CBMC-2 formed through non-covalent interactions shows packing parameters corresponding to the ideal polymerization parameters. UV-vis, DSC and X-ray analyses indicated that the crystals of macrocycle CBMC-2 could undergo diacetylene topochemical polymerization inside the solid by heating. This was confirmed using Raman spectroscopy and solid-state ¹³C NMR spectroscopy. This work provides a method for synthesizing carborane supramolecular polymers.