Base-metal copper( ii ) complexes derived from unsymmetrical salen-type ligands were designed and synthesized using ligands L ¹ H to L ⁴ H. These complexes were employed as catalysts for [3+2] cycloaddition and A ³ -coupling reactions.

The efficient removal of organic contaminants from wastewater is, nowadays, a prominent area of study due to its biological as well as environmental significance. Antibiotics are now found in wastewater because of their high use, which has become a source of aquatic pollution. These antibiotics have dangerous implications for people’s health. Hence, effective pharmaceutical removal from wastewater and contaminated water bodies, especially the removal of antibiotics, is of major interest to global research organizations. This is why it is necessary to investigate this class of toxic material in wastewater discharge. We synthesized three different coordination polymers (CPs) in the presence of various assistant carboxylate linkers, namely, [Zn(Hbtc)(dip)]_n (1), [Zn₄(1,2-bdc)₄(dip)₄]_n (2), and [Zn(1,4-bdc)(dip)]_n (3) (3,5-di(1H-imidazol-1-yl)pyridine = dip, 1,3,5-benzenetricarboxylic acid = H₃btc, 1,2-benzenedicarboxylic acid = 1,2-H₂bdc, and 1,4-benzendicarboxylic acid = 1,4-bdc). These CPs were characterized by using different techniques, including single-crystal X-ray diffraction. The structural studies demonstrated that in 2, there are four Zn(II) centers and both centers are in different coordination environments (Zn2 has distorted tetrahedral geometry, whereas Zn1, Zn3, and Zn4 have square pyramidal geometry). Hirshfeld surfaces analysis revealed that different types of intermolecular interactions (C⋯C, H⋯C, H⋯H, O⋯C, N⋯H, and O⋯H) are present in the synthesized CPs. We examined the different antibiotics, such as metronidazole (MDZ), nitrofurazone (NFZ), dimetridazole (DTZ), sulfasalazine(SLA), and oxytetracycline (OXY), degradation behaviors of the synthesized CPs, which showed remarkable degradation efficiency. 1 showed photocatalytic behavior toward the NFZ antibiotic in an aqueous media. This study also showed that these catalysts are stable and reusable under mild conditions.

Four new Ni( ii ) coordination polymers (1–4) have been successfully synthesized using 5,5′-(ethene-1,2-diyl)diisophthalic acid (H ₄ L) and different N-donor ancillary ligands. Furthermore, the magnetic properties of 1–4 were investigated in detail.

The incremental use of herbicides is now posing a pollution problem in aquatic systems. Therefore, it is necessary to decompose this class of harmful components existing in wastewater. Metal–organic frameworks (MOFs) are a peculiar class of multidimensional materials that can be employed as a photocatalyst to decompose pesticides present in the wastewater discharged. For this we have synthesized three high-stability Co(II)-based metal organic frameworks (MOFs) [Co(H₂L)(bb)·DMF]_n (1), [Co(L)_0.5(bb)]_n (2), and [NH₂(CH₃)₂][Co₂(μ₃-OH)(L)(bb)] (3), where H₄L = 5,5′-(1,2-phenylenebis(methyleneoxy)diisophthalic acid and bb = 4,4′-bis(imidazolyl)biphenyl. These MOFs are characterized by thermal analyses and single-crystal X-ray diffraction. 1 features a new 3D, 2-nodal 4,4-connected network with a Schläfli symbol of (4⁴·6²). 2 displays a 3D, 4,4-c network, with a Schläfli symbol (6⁴·8²). 3 shows a 3D two nodal (3,8) connected net with a Schläfli symbol (4³)₂(4⁶·6¹⁸·8⁴). 1–3 are semiconducting in nature with E_g of 3.31 eV, 2.95 eV, and 3.25 eV, respectively. These three MOFs show high catalytic activities for the degradation of different pesticides, including four common pesticides thiabendazole (TBZ), dinotefuran (DTF), metamitron (MMT), and ciprofloxacin (CIP) in an aqueous solution. TBZ shows photocatalytic degradation by the synthesized MOF, which demonstrated 89% degradation. Moreover, the possible photodegradation mechanism was proposed and explored by a radical tapping experiment. The Hirshfeld surfaces study demonstrated that these synthesized coordination polymers contain various forms of intermolecular contacts (C⋯C, H⋯C, H⋯H, and O⋯H).