Hydrothermal preparation, crystal structure, Hirshfeld surface analysis, photophysical properties and antifungal activity of a series of complexes assembled by 5-bromo-2-(carboxymethoxy)benzoic acid ligands

Abstract

Five complexes [Co(BCBA)(H2O)3]n (1), [Co(BCBA)(4,4′-Bipy)2·(H2O)]n (2), [Cu(BCBA)(H2O)]n (3), [Zn(BCBA)(H2O)]n (4) and [Cd(BCBA)(2,2′-Bipy)(H2O)·(H2O)]n (5) (H2BCBA= 5‑bromo-2-(carboxymethoxy)benzoic acid, 4,4′-Bipy = 4,4′-bipyridine and 2,2′-Bipy = 2,2′-bipyridine) have been synthesized with H2BCBA ligand by solvothermal condition. All the complexes have been structurally characterized by infrared spectra (IR), elemental analyses and single-crystal X-ray diffraction analyses. Complex 1 is a zero-dimensional structure, and complexes 2–5 are one-dimensional chain structure. Furthermore, thermogravimetric analyses (TGA), Hirshfeld surface analysis, photo-luminescence properties, Solid-state UV–Vis diffuse reflectance spectroscopy and antifungal activity for complexes 1–5 were investigated. The reciprocal H···O/H/Br/C contacts dominate over 86 % of total Hirshfeld surface. Complexes 1–5 have certain inhibitory effects on 8 pathogenic fungi. Among them, complex 5 has the strongest antibacterial activity against Rhizoctonia solani AG1, Sphaeropsis sapinea and Colletotrichum fructicola, and the inhibitory rate reached 100 %.