Mononuclear Copper(I) 3-(2-pyridyl)pyrazole Complexes: The Crucial Role of Phosphine on Photoluminescence.
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ABSTRACT:
SUBMITTER: Baranova KF
PROVIDER: S-EPMC8620892 | biostudies-literature |
REPOSITORIES: biostudies-literature
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Project description:Two naphthalene pyrazole ligands were synthesized using KOH/DMSO and Cu catalyst and characterized with FT-IR, ESI-MS, 1H, and 13C NMR spectroscopies. The crystal structures of 1-(2-methylnaphthalen-1-yl)-1H-pyrazole (MeNap-Pz) ligand have been determined with X-ray crystal structure analysis. Reaction of the ligands with Cu(NO3)2x3.5H2O gave two new complexes and characterized with magnetic susceptibility, molar conductance, FT-IR, LCMS-MS, ICP-OES, NMR, thermogravimetric analysis, and ESR spectra. The spectral data of the ligands are coordinated to the metal ion through the nitrogen atoms of the pyrazole ring. Consequently, it has been determined that [Cu(MeNap-Pz)2(NO3)]NO3.2H2O complex showed square planar geometry and [Cu(NapMe-Pz)2(NO3)2].H2O complex showed octahedral geometry. All compounds were screened for in vitro antibacterial activity and copper complexes have been shown to be effective on bacteria.
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Project description:Two novel copper(II) complexes of formulas {[Cu(4-Hmpz)4][Cu(4-Hmpz)2(µ3-ox-κ2O1,O2:κO2':κO1')(ClO4)2]}n (1) and {[Cu(3,4,5-Htmpz)4]2[Cu(3,4,5-Htmpz)2(µ3-ox-κ2O1,O2:κO2':κO1')(H2O)(ClO4)]2[Cu2(3,4,5-Htmpz)4(µ-ox-κ2O1,O2:κ2O2',O1')]}(ClO4)4·6H2O (2) have been obtained by using 4-methyl-1H-pyrazole (4-Hmpz) and 3,4,5-trimethyl-1H-pyrazole (3,4,5-Htmpz) as terminal ligands and oxalate (ox) as the polyatomic inverse coordination center. The crystal structure of 1 consists of perchlorate counteranions and cationic copper(II) chains with alternating bis(pyrazole)(µ3-κ2O1,O2:κO2':κO1'-oxalato)copper(II) and tetrakis(pyrazole)copper(II) fragments. The crystal structure of 2 is made up of perchlorate counteranions and cationic centrosymmetric hexanuclear complexes where an inner tetrakis(pyrazole)(µ-κ2O1,O2:κ2O2',O1'-oxalato)dicopper(II) entity and two outer mononuclear tetrakis(pyrazole)copper(II) units are linked through two mononuclear aquabis(pyrazole)(µ3-κ2O1,O2:κO2':κO1'-oxalato)copper(II) units. The magnetic properties of 1 and 2 were investigated in the temperature range 2.0-300 K. Very weak intrachain antiferromagnetic interactions between the copper(II) ions through the µ3-ox-κ2O1,O2:κO2':κO1' center occur in 1 [J = -0.42(1) cm-1, the spin Hamiltonian being defined as H = -J∑S1,i · S2,i+1], whereas very weak intramolecular ferromagnetic [J = +0.28(2) cm-1] and strong antiferromagnetic [J' = -348(2) cm-1] couplings coexist in 2 which are mediated by the µ3-ox-κ2O1,O2:κO2':κO1' and µ-ox-κ2O1,O2:κ2O2',O1' centers, respectively. The variation in the nature and magnitude of the magnetic coupling for this pair of oxalato-centered inverse copper(II) complexes is discussed in the light of their different structural features, and a comparison with related oxalato-centered inverse copper(II)-pyrazole systems from the literature is carried out.
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