Hydroxylation of isophthalic acid in the hydrothermal reaction of CuII-isophthalate system – Syntheses and crystal structures of two coordination polymers

The reaction of isophthalic acid (H2ip) and copper nitrate under hydrothermal condition produced an in situ synthesized ligand 2-hydroxy isophthalic acid (or 2,6-dicarboxyl phenol, H3ipO) derived from H2ip without the presence of N-heterocyclic ligands. The hydroxylation was controlled by the temperature of hydrothermal synthesis. Two coordination polymers, {[Cu5(OH)2(ip)(ipO)2] · (H2O)}n (1) and [Cu3(ipO)2(H2O)2]n (2) were synthesized and characterized by X-ray crystallography, IR spectra and elemental analyses. Complex 1 was assembled with both the original ligand and the in situ synthesized ligand.