Layer Geometry Modulation in Cu(II) Coordination Networks Based on Disubstituted Bis(imidazolyl)benzene Ligands

The structural chemistry of two‐dimensional Cu(II) coordination networks constructed from ring‐disubstituted bis(imidazolyl)benzene ligands has been investigated in order to elucidate the combined influence of ligand functionalization and counteranion identity on layer geometry, packing, and framework stability. The dimethyl‐substituted ligand ( bibMe 2 ) affords three closely related layered frameworks when combined with copper(II) nitrate ( UdP‐8‐NO 3 ), copper(II) perchlorate ( UdP‐8‐ClO 4 ), or copper(II) tetrafluoroborate ( UdP‐8‐BF 4 ), leading to new compounds of formula [Cu( bibMe 2 ) 2 (X) 2 ]·nSolv (X = NO 3 , ClO 4 or BF 4 ). UdP‐8‐NO 3 and UdP‐8‐ClO 4 were obtained both in single crystal and powder form. On the other hand, UdP‐8‐BF 4 could only be isolated as a powder. UdP‐8‐NO 3 and UdP‐8‐ClO 4 are isoreticular at the local coordination level, showing a sql topology, but display markedly different layer arrangements, stacking modes, interlayer separations, and accessible void volumes. These structural differences translate into a pronouncedly different response to external stimuli, as revealed by PXRD‐based stability tests under humidity, vacuum, and variable temperature conditions. Extension to a methoxy‐disubstituted ligand ( bibOMe 2 ) yields single crystals of a further two‐dimensional Cu(II) network describable with a formula [Cu( bibOMe 2 ) 2 (ClO 4 ) 2 ] ( UdP‐9‐ClO 4 ). This compound could only be isolated as single crystals; therefore, no further characterization was carried out.