The title compound (abbreviated as llPzAPH) has been synthesised and physico-chemically (IR, PMR, mass spectra) characterized for the first time. The coordinating behaviour of the thiosemi-carbazone has been investigated by isolation and characterization of its complexes with Co(ill), Ni(ll) and Gu(ll) having different counterions, Magnetic and spectral data indicate CoO’lPzAPjX (X = counter ion) as spin paired octahedral species with the ligand in the deprotonated thiol form, while Ni(MPzAPH) X and APH) Xareproposed to be spin-free octahedral with the ligand in the neutral thione form. A spin-paired diamagnetic Ni(MPzAP) (SCN) has also been identified. IR data point out that the pyrazolyl ring nitrogen (tertiary), the azomethine nitrogen and the sulphur atom are the points of attachment With the metal ion in all these complex species. © 1984, Taylor &amp; Francis Group, LLC. All rights reserved.

N SAHA

N MUKHERJEE

University of Calcutta (informally known as Calcutta University or CU) is a collegiate public state university located in Kolkata, West Bengal, India.&nbsp;Within India it is recognized as a &quot;Five-Star University&quot; and accredited &quot;A&quot; Grade by National Assessment and Accreditation Council.

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The University of Calcutta has secured the Fifth position among the Universities of India in the prestigious &quot;Indian University Ranking 2019&quot; list, released by the NIRF of the Ministry of Human Resource Development, Government of India.

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It was established on 24 January 1857, and was one of the first institutions in Asia to be established as a multidisciplinary and Western-style university. Its alumni and faculty include several heads of state, heads of government, social reformers, prominent artists, only academy award winner and Dirac medal winner in India, many Fellows of the Royal Society and five Nobel laureates as of 2019 which is highest in South Asia.

University Of Calcutta

Ligational Behaviour of a New Pyrazole Derived Thiosemicarbazone, a Potential Antiviral Agent: Cobalt(III), Nickel(II) and Copper(II) Complexes of Neutral and Deprotonated 5(3)-Methylpyrazole-3(5)-aldehydo-4-phenylthiosemicarbazone

Synthesis and Reactivity in Inorganic and Metal-Organic Chemistry

The coordinating properties of the title ligand, 5-methyl-3-formyl pyrazole 3-hexamethyleneiminyl thiosemicarbazone (HMPz3Hex), synthesized and characterized (elemental analysis, MS, IR, 1H and 13C NMR and X-ray crystallography) for the first time, are reported by solid-state isolation of cobalt(III) complexes, [Co(MPz3Hex)2]X·nH 2O (X=Cl, Br, NO3, ClO4 or BF4; n=1to2). The reported complex species have been spectroscopically characterized with X-ray structural identification of [Co(MPz3Hex)2] Br·H2O. IR and NMR data (1H and 13C) for the free ligand and its CoIII complexes confirm that the ligand, HMPz3Hex, behaves as a uninegative anion with NNS tridentate function via the pyrazolyl tert-nitrogen, azomethine nitrogen and thiol sulfur. Electronic spectral data recommend a distorted octahedral environment for the six-coordinate CoIII species. X-ray crystallography of [Co(MPz3Hex)2]Br·H2O (C2/c, monoclinic), has shown unambiguously that the crystallographic asymmetric unit consists of a [Co(MPz3Hex)2]+ cation and one Br- anion with one H2O molecule as solvent of crystallization. The two NNS ligands coordinate orthogonally to the central CoIII ion with mer-configuration. A critical scrutiny of the X-ray data of free HMPz3Hex (Pna21, orthorhombic) and [Co(MPz3Hex)2]Br·H 2O indicates that an unusual rotation about the azomethine (C=N) double bond occurs during complexation with CoIII. A plausible reaction mechanism for the same has been proposed. Sulfur is involved in a C(7)-H(7)⋯S(1) intramolecular contact restricting the conformation of the ligand both in free and its complexed form. © 2003 Elsevier Ltd. All rights reserved.

Polyhedron

Synthesis and spectroscopic characterization of new cobalt(III) complexes with 5-methyl-3-formyl pyrazole 3-hexamethyleneiminyl thiosemicarbazone (HMPz3Hex): X-ray crystallographic identification of HMPz3Hex and [Co(MPz3Hex)2]BrÂ·H2O with evidence for unu

The coordination behaviour of the title ligand, 5-methyl-3-formylpyrazole N(4)-benzyl-N(4)-methylthiosemicarbazone (HMPz4BM), is reported with solid state isolation of copper(II) complexes, [Cu(HMPz4BM)X2] (X = Cl, Br, NO3, ClO4 and BF4) which have been spectroscopically and structurally characterised. I.r. data for the free ligand and its Cu(II) complexes indicate that HMPz4BM exhibits a neutral NNS tridentate function via the pyrazolyl nitrogen(tertiary), azomethine nitrogen and thione sulphur. Electronic spectral data are suggestive of a square pyramidal environment for the seemingly pentacoordinated Cu(II) species. E.s.r parameters (RT and LNT) of the reported copper(II) complexes are indicative of a dx2-y2 ground state for the reported species. Cyclic voltammograms of Cu(II) complexes show a quasireversible CuII/CuIII couple and also an irreversible CuII/CuI couple. X-ray crystallography of a representative species, [Cu(HMPz4BM)(NO3)2] (C2/c, monoclinic), has unambiguously documented the conjectural findings from i.r. data that coordinating sites of the title ligand are pyrazolyl (tertiary) nitrogen, azomethine nitrogen and the thione sulphur (NNS); and the oxygen of one of the nitrate ions has occupied the basal plane; the fifth coordination position has been occupied by the oxygen of another nitrate ion in a square pyramidal geometry. The antibacterial properties of the ligand and its copper(II) complexes studied on microoranism, Staphylococcus aureus have pointed out that most of the complexes have higher activities than that of the free ligand.

Molecular and Cellular Biochemistry

Spectroscopic, structural and antibacterial properties of copper(II) complexes with bio-relevant 5-methyl-3-formylpyrazole N(4)-benzyl-N(4)-methylthiosemicarbazone

Two new cobalt(III) complexes with S-benzyl-β-N-(5-methylpyrazole-3-yl)methylenedithiocarbazate (H2L), [Co(HL)2]NO3·EtOH (1) and [Co(HL)(L)]·H2O (2), have been synthesised and characterised using single-crystal X-ray diffraction and spectroscopic (electronic, IR and NMR) techniques. The structure of 1 consists of [Co(HL)2]+ cation and NO3-anion linked by an ethanol solvent molecule, that of 2 consists of neutral monomeric species [Co(HL)(L)] with one mole water of crystallisation where the two ligand molecules are uniquely non-equivalent. In both the complexes the coordination geometry about cobalt is distorted octahedral and the two ligands are in the mer configuration (S and tertiary N atom cis to each other and the iminic N atoms trans). © 2002 Elsevier Science Ltd. All rights reserved.

Synthesis and spectroscopic characterisation of cobalt(III) complexes with S-benzyl-Î²-N-(5-methylpyrazole-3-yl)methylenedithiocarbazate (H 2 L): X-ray structures of [Co(HL) 2 ]NO 3 Â·EtOH (1) and [Co(HL)(L)]Â·H 2 O (2)

The coordination mode of the title ligand, HMPzSB (synthesized for the first time and characterised by elemental analysis, mass, IR and PMR spectral parameters), is reported by solid state isolation and physicochemical identification of cobalt(III) complexes, [Co(MPzSB)2]X (X = Cl, ClO4 and BF4). Electronic spectral features of these diamagnetic CoIII species classify them as six-coordinate distorted octahedral ones. IR spectra (4000-200 cm-1) of HMPzSB and its complexes are indicative of an uninegative tridentate NNS function of the title ligand through the Pyrazolyl (2N) nitrogen, azomethine nitrogen and thiolato sulphur atom. 1H-NMR data (in d6-DMSO at 300 MHz) of the uncomplexed ligand and its CoIII species are commensurate with the tridenticity (NNS) of the deprotonated form of HMPzSB. X-ray crystallographic studies of [Co(MPzSB)2]Cl has authenticated that the geometry of the species is distorted octahedral, as envisaged, with the two deprotonated primary ligand systems (MPzSB-). The Co - N (azomethine) and Co - N (pyrazolyl) bond lengths are 1.898(4) &amp; 1.954(5) Å and 1.903(4) &amp; 1.916(5) Å in ligand A &amp; B, respectively where as that of Co - S (thiolato) is 2.217(2) and 2.255(2) Å in the two ligands. The extended planarity of the dithiocarbazate moiety and the pyrazolyl ring of the primary ligand system are maintained because of the ligation phenomenon to CoIII. © 1997 Elsevier Science Ltd.

Synthesis and spectroscopic characterisation of cobalt(III) complexes with S-benzyl dithiocarbazate of 5-methyl-3-formyl pyrazole (HMPzSB) : X-ray crystal structure of [Co(MPzSB)2]Cl

European Journal of Inorganic Chemistry

Spotlights on our sister journals: Eur. J. Inorg. Chem. 3/2016

Die Makromolekulare Chemie

10.1002/macp.1972.021580107

Inorganic Chemistry

Pyrazoles and imidazoles as ligands. XIV. Crystal and molecular structure of dibromotetrakis(5-methylpyrazole)manganese(II), Mn(C4H6N2)4Br2

J. Chem. Soc. D

Diazabullvalene; a “nonclassical” molecule?

Acta Crystallographica Section B Structural Crystallography and Crystal Chemistry

The crystal and molecular structure of hexapyrazolenickel(II) nitrate, Ni(C3H4N2)6(NO3)2

Ligational Behaviour Of A New Pyrazole Derived Thiosemicarbazone, A Potential Antiviral Agent: Gobalt(Iii), Nickel(Ll) And Copper(Ll) Complexes Of Neutral And Deprdtonated 5(3) -Methylpyrazole-3(5) -Aldehydo-4-Piienylth10Semicarbazone

Journal	Synthesis and Reactivity in Inorganic and Metal-Organic Chemistry
Publisher	-
ISSN	0094-5714