Halogenated tennimides and trezimides: impact of halogen bonding and solvent role on porous network formation and inclusion

Abstract

Fluorine and chlorine derived macrocycles (FIO)_3/4 and (ClIO)_3/4 are synthesised from the reaction of isophthaloyl dichloride with 2-amino-5-fluoropyridine and 2-amino-5-chloropyridine, respectively. Solvents of crystallisation are present in the six F/Cl crystal structures and occupy 12–43% of crystal lattice. Halogenated solvents (CH₂Cl₂; CHCl₃) typically link macrocycles through halogen and hydrogen bonding interactions forming 1-D chains through halogen bonding, whereas dimethylsulfoxide (DMSO) incorporation promotes solvent channel formation. For (ClIO)₃, the total (%) solvent comprising DMSO and water molecules is 43% of the structure volume with 3.5(DMSO)·3(H₂O) per (ClIO)₃ macrocycle resulting in extensive channel formation. The solvent channel aggregation assists 2-D network formation in combination with short C–Cl⋯OC halogen bonding interactions and C–Cl⋯Cl–C contacts (Cl⋯O, Cl⋯Cl; both N_c = 0.90). Of further note is that (ClIO)₄·CH₂Cl₂ is isomorphous with two methylated analogues (MIO)₄·CH₂Cl₂ and (MIO)₄·CHCl₃.