Solution and Mechanochemical Syntheses of Two Novel Cocrystals: Ligand Length Modulated Interpenetration of Hydrogen-Bonded 2D 63-hcb Networks Based on a Robust Trimeric Heterosynthon

Abstract

Cocrystallization of a versatile organic tecton, 3,3′,5,5′-tetramethyl-4,4′-bipyrazole (tmbpz), with aliphatic dicarboxylic acid suberic acid (H2sub) and sebacic acid (H2seb) generates two supramolecular solids [(tmbpz)2·(H2sub)] (1) and [(tmbpz)2·(H2seb)] (2). In the present case, both cocrystals could be obtained from either solution evaporation or mechanochemical solid-state reaction. Single-crystal structural analyses reveal that the 1 and 2 are 4-fold and 5-fold 2D → 2D parallel interpenetrated 63-hcb networks, respectively. The substantial dissimilarities in the degree of interpenetration are modulated by the different lengths of dicarboxylic acids. The thermal stabilities and photoluminescence behaviors of them were also discussed.