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

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)center dot 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 center dot center dot center dot O=C halogen bonding interactions and C-Cl center dot center dot center dot Cl-C contacts (Cl center dot center dot center dot O, Cl center dot center dot center dot Cl; both N-c = 0.90). Of further note is that (ClIO)(4)center dot CH2Cl2 is isomorphous with two methylated analogues (MIO)(4)center dot CH2Cl2 and (MIO)(4)center dot CHCl3.