Synthesis, structure and properties of a novel self-assembled tetranuclear copper(II) complex derived from carboxylate-based multidentate ligand

• Published in: Inorganic chemistry communications 2020-11, Vol.121, p.108208, Article 108208
• Main Authors: Dutta, Nityananda, Haldar, Shobhraj, Majumder, Avishek, Vijaykumar, Gonela, Carrella, Luca, Bera, Manindranath
• Format: Article
• Language: English
• Subjects: Carboxylate bridge; Crystal structure; Magnetic property; Multidentate ligand; Tetracopper complex; TGA analysis
• ISSN: 1387-7003; 1879-0259
• DOI: 10.1016/j.inoche.2020.108208

A novel self-assembled tetranuclear copper(II) complex, [Cu(H2O)5][Cu4(cpdp)2(adip)]ClBr∙2CH3OH·8H2O (1) has been successfully prepared by exploiting the flexibility, chelating ability and bridging potential of a carboxylate-based multidentate ligand, H3cpdp, and structurally characterized. The tetranuclear complex was investigated for its magnetic and thermal properties. [Display omitted] •A novel tetranuclear copper(II) complex has been synthesized and structurally characterized.•Adipate group shows a μ4:η1:η1:η1:η1 bridging mode connecting four copper(II) ions.•Copper(II) ions are coupled antiferromagnetically.•The complex is thermally stable up to ∼200 °C. A novel tetranuclear copper(II) complex, [Cu(H2O)5][Cu4(cpdp)2(adip)]ClBr∙2CH3OH·8H2O (1) of carboxylate-based symmetrical multidentate ligand, H3cpdp [H3cpdp = N,N'-Bis[2-carboxybenzomethyl]-N,N'-Bis[2-pyridylmethyl]-1,3-diaminopropan-2-ol; adip = adipate], has been synthesized and fully characterized. Complex 1 has been synthesized by carrying out reaction of ligand H3cpdp with stoichiometric amounts of CuCl2·2H2O/Na2(CH2CH2COO)2 in methanol-water in the presence of NaOH at room temperature. The solid state structure of 1 consists of a [Cu4(µ4-adip)] core unit which is held together by two multidentate bridging ligands, cpdp3−. In fact, complex 1 can be viewed as a “dimer-of-dimers” generated by self-assembly of two [Cu2(cpdp)]+ units exclusively bridged by one adipate group in a μ4:η1:η1:η1:η1 fashion. Variable-temperature (2–300 K) magnetic susceptibility measurements disclose the presence of antiferromagnetic interactions among the copper(II) ions. Thermal behaviour of 1 has been investigated by thermogravimetric analysis specifying that the complex is stable up to ∼200 °C.