From helix to helical pores: solid-state crystalline conversions triggered by gas–solid reactions

Abstract

Two one-dimensional (1D) helical coordination polymers, CuBIm–Cl and CuBIm–Br (BIm = 1,2-bis((5H-imidazol-4-yl)-methylene)hydrazine), are constructed from Cu²⁺ ions, halides and mono-deprotonated BIm. Solid-state crystalline conversions of CuBIm–Cl and CuBIm–Br to a gyroidal metal–organic framework (MOF) STU-3 which is composed of Cu ions and Bim ligands are observed through a gas–solid reaction, where the gas is methylamine.