Cobalt Complexes Appended with <i>para</i>- and <i>meta</i>-Arylcarboxylic Acids: Influence of Cation, Solvent, and Symmetry on Hydrogen-Bonded Assemblies

The present work shows the syntheses, structures, and hydrogen-bonding-based self-assembly of Co3+ coordination complexes containing appended arylcarboxylic acid groups. The carboxylic acid groups are present at either the para or the meta position of the appended arene ring. Every Co3+ coordination complex offers both hydrogen-bond donors (in O–H groups of arylcarboxylic acid) and acceptors (in COamide groups as well as COacid of arylcarboxylic acid) in a single molecule. As a consequence, all molecules self-assemble in a highly complementary and unique structural fashion via an array of inter- and intramolecular hydrogen bonding. The position of carboxylic acid, presence of cation, type of cation, and solvent of crystallization has significantly affected/altered the self-assembly process of complementary functional groups.