A dinuclear copper(II) complex, (μ2-MeOH)bis(μ2-phenoxide)dicopper complex with N-(3-aminopropyl)salicylaldimine, has been synthesised and characterised by X-ray structure determination. Variable temperature magnetic susceptibility measurement shows that it is strongly antiferromagnetically coupled. © 2003 Elsevier Science B.V. All rights reserved.

ASHUTOSH GHOSH

Chemistry

M S RAY

G MUKHOPADHYAY

M G B DREW

T -H LU

S CHAUDHURI

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.

&nbsp;

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.

&nbsp;

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

A diphenoxo bridged antiferromagnetically coupled dimer of copper(II) having bridging methanol

Inorganic Chemistry Communications

Two phenoxido bridged dinuclear Cu(II) complexes, [Cu2(L 1)2(NCO)2] (1), and [Cu2(L 2)2(NCO)2]·2CH3OH (2), have been synthesized using the tridentate reduced Schiff-base ligands 2-[(2-dimethylamino-ethylamino)-methyl]-phenol (HL1) and 2-[(2-diethylamino-ethylamino)-methyl]-phenol (HL2) respectively. Re-crystallization of compound 2 from dichloromethane produced desolvated complex [Cu2(L2)2(NCO)2] (3). The compounds 2 and 3 are pseudopolymorphs or solvomorphs which differ in the crystal system (orthorhombic, Pbca for 2 and monoclinic, P21/n for 3). The complexes have been characterized by X-ray structural analyses and spectroscopic methods. In all three complexes Cu(II) is penta-coordinated having the geometry intermediate between distorted square pyramid and trigonal bipyramid with Addison parameter (τ) = 0.33, 0.48 and 0.53 for 1, 2 and 3 respectively. Using 3,5-di-tert-butylcatechol (3,5-DTBC) as the substrate, the catecholase activity of complexes 1 and 2 has been studied in methanol solution; compound 2 shows slightly higher catecholase activity (kcat = 98.4h 1) than compound 1 (kcat = 64.2 h 1). © 2013 Elsevier Ltd. All rights reserved.

Polyhedron

Solvomorphism and catecholase activities of bis(Î¼-phenoxido) dicopper(II) complexes

Two octahedral complexes [Ni(HL1)2](ClO4)2 (1) and [Ni(HL2)2](ClO4)2 (2) and a square planar complex [Ni(HL3)]ClO4 (3) have been prepared, where [HL1 = 3-(2-amino-ethylimino)-butan-2-one oxime, HL2 = 3-(2-amino-propylimino)butan-2-one oxime] and H2L3 = 3-[2-(3-hydroxy-1-methyl-but-2-enylideneamino)-1-methyl-ethylimino]-buta n-2-one oxime. All the complexes have been characterized by elemental analyses, spectral studies and room temperature magnetic moment measurements. The molecular structures of all three compounds were elucidated on the basis of X-ray crystallography; complexes 1 and 2 are seen to be the mer isomers. © 2008 Elsevier Ltd. All rights reserved.

Syntheses, characterization and X-ray crystal structures of Ni(II) complexes of tridentate monocondensed and tetradentate dicondensed Schiff bases

Two sets of ligands, set-1 and set-2, have been prepared by mixing 1,3-diaminopentane and carbonyl compounds (2-acetylpyridine or pyridine-2-carboxaldehyde) in 1:1 and 1:2 ratios, respectively, and employed for the synthesis of complexes with Ni(II) perchlorate, Ni(II) thiocyanate and Ni(II) chloride. Ni(II) perchlorate yields the complexes having general formula [NiL2](ClO4)2(L = L1 [N3-(1-pyridin-2-yl-ethylidene)-pentane-1,3-diamine] for complex 1 or L2[N3-pyridin-2-ylmethylene-pentane-1,3-diamine] for complex 2) in which the Schiff bases are monocondensed terdentate, whereas Ni(II) thiocyanate results in the formation of tetradentate Schiff base complexes, [NiL(SCN)2] (L = L3[N,N′-bis-(1-pyridin-2-yl-ethylidine)-pentane-1,3-dia mine] for complex 3 or L4 [N,N′-bis(pyridin-2-ylmethyline)-pentane-1,3-diamine] for complex 4) irrespective of the sets of ligands used. Complexes 5 {[NiL3(N3)2]} and 6 {[NiL4(N3)2]} are prepared by adding sodium azide to the methanol solution of complexes 1 and 2. Addition of Ni(II) chloride to the set-1 or set-2 ligands produces [Ni(pn)2]Cl2, 7, as the major product, where pn = 1,3-diaminopentane. Formation of the complexes has been explained by the activation of the imine bond by the counter anion and thereby favouring the hydrolysis of the Schiff base. All the complexes have been characterized by elemental analyses and spectral data. Single crystal X-ray diffraction studies confirm the structures of three representative members, 1, 4 and 7; all of them have distorted octahedral geometry around Ni(II). The bis-complex of terdentate ligands, 1, is the mer isomer, and complexes 4 and 7 possess trans geometry. © 2008 Elsevier B.V. All rights reserved.

Inorganica Chimica Acta

Nickel(II) complexes of terdentate or symmetrical tetradentate Schiff bases: Evidence of the influence of the counter anions in the hydrolysis of the imine bond in Schiff base complexes

Bis(o-hydroxyacetophenone)nickel(II) dihydrate, on reaction with 1,3-pentanediamine, yields a bis-chelate complex [NiL2] ·2H2O (1) of mono-condensed tridentate Schiff base ligand HL {2-[1-(3-aminopentylimino)ethyl]phenol}. The Schiff base has been freed from the complex by precipitating the NiII as a dimethylglyoximato complex. HL reacts smoothly with Ni(SCN)2·4H2O furnishing the complex [NiL(NCS)] (2) and with CuCl2·2H2O in the presence of NaN3 or NH4SCN producing [CuL(N 3)]2 (3) or [CuL(NCS)] (4). On the other hand, upon reaction with Cu(ClO4)2·6H2O and Cu(NO3)2·3H2O, the Schiff base undergoes hydrolysis to yield ternary complexes [Cu(hap)(pn)(H2O)]ClO 4 (5) and [Cu(hap)(pn)(H2O)]NO3 (6), respectively (Hhap = o-hydroxyacetophenone and pn = 1,3-pentanediamine). The ligand HL undergoes hydrolysis also on reaction with Ni(ClO4) 2·6H2O or Ni(NO3)2· 6H2O to yield [Ni(hap)2] (7). The structures of the complexes 2, 3, 5, 6, and 7 have been confirmed by single-crystal X-ray analysis. In complex 2, NiII possesses square-planar geometry, being coordinated by the tridentate mono-negative Schiff base, L and the isothiocyanate group. The coordination environment around CuII in complex 3 is very similar to that in complex 2 but here two units are joined together by end-on, axial-equatorial azide bridges to result in a dimer in which the geometry around CuII is square pyramidal. In both 5 and 6, the CuII atoms display the squarepyramidal environment; the equatorial sites being coordinated by the two amine groups of 1,3-pentanediamine and two oxygen atoms of o-hydroxyacetophenone. The axial site is coordinated by a water molecule. Complex 7 is a square-planar complex with the Ni atom bonded to four oxygen atoms from two hap moieties. The mononuclear units of 2 and dinuclear units of 3 are linked by strong hydrogen bonds to form a one-dimensional network. The mononuclear units of 5 and 6 are joined together to form a dimer by very strong hydrogen bonds through the coordinated water molecule. These dimers are further involved in hydrogen bonding with the respective counteranions to form 2-D net-like open frameworks. © Wiley-VCH Verlag GmbH &amp; Co. KGaA, 2008.

European Journal of Inorganic Chemistry

Anion-directed template synthesis and hydrolysis of mono-condensed Schiff base of 1,3-pentanediamine and o-hydroxyacetophenone in NiII and CuII complexes

A novel trinuclear nickel(II) complex, [Ni3(L)2(H2O)2](ClO 4)2, where L is a bridging unsymmetrical tetradentate ligand, involving o-phenylenediamine, diacetyl monoxime and acetylacetone (H2L = 4-[2-(3-hydroxy-1-methyl-but-2-enylideneamino)-phenylimino]-pentan-2-one oxime) has been synthesized and characterized structurally. In the complex, an octahedral Ni(II) centre is held in the middle by two square planar units with the aid of oxime and ketonic bridges. © 2007 Elsevier B.V. All rights reserved.

A novel trinuclear nickel(II) complex of an unsymmetrical tetradentate ligand involving bridging oxime and acetylacetone functions

Acta Crystallographica Section A Foundations of Crystallography

An empirical method for correcting diffractometer data for absorption effects

J. Chem. Soc., Dalton Trans.

Antiferromagnetism induced by successive protonation of terminal phenol groups of a bis(μ-phenoxide)-bridged dicopper(ii,ii) complex

Chemistry - A European Journal

From Tetranuclearµ4-Oxo toµ4-Peroxocopper(II) Complexes

Inorganic Chemistry

Structural Modeling and Magneto−Structural Correlations for Hydroxo-Bridged Copper(II) Binuclear Complexes

Magnetostructural Correlations in Bis(μ2-phenoxide)-Bridged Macrocyclic Dinuclear Copper(II) Complexes. Influence of Electron-Withdrawing Substituents on Exchange Coupling

Journal	Data powered by TypesetInorganic Chemistry Communications
Publisher	Data powered by TypesetElsevier B.V.
ISSN	1387-7003
Open Access	No