The present study deals with the syntheses, characterization and crystal structures of six compounds of composition [CuIILZnII(SCN)2] (1), [CuIILZnII(N3)2] (2), [{CuIILZnII(dca)}2(µ1,5-dca)2] (3), [CuIILCdII(SCN)2] (4), [{CuIILCdII(N3)}2(µ1,1-N3)2] (5) and [{CuIILCdII(dca)}{CuIILCdII}{CuII(MeCN)LCdII}(µ1,5-dca)5]n (6), where H2L = N,N′-bis(3-ethoxysalicylidene)-1,4-butanediamine and dca = dicyanamide. Either the compound itself or the basic unit in the compound in 1–6 is diphenoxo-bridged dinuclear CuIIZnII or CuIICdII moiety. There is one deprotonated ligand, L2−, per dinuclear unit. Copper(II) occupies the N(imine)2O(phenoxo)2 compartment while zinc(II) or cadmium(II) occupies O(phenoxo)2O(ethoxy)2 compartment of L2−. Thiocyanate in 1 and 4 and azide in 2 behave as monodentate (terminal) ligands, so these three compounds are dinuclear systems. On the other hand, dinuclear units are assembled by μ1,5-dca in 3 and 6 and μ1,1-azide in 5 to generate either dimer-of-dinuclear type tetrametallic clusters (3 and 5) or a one-dimensional coordination polymer (6). Notably, compound 6 represents a new type of coordination polymer. The geometries of the metal ions have been understood from SHAPE analyses. Regarding one pentacoordinated environment, contradiction is observed between the conclusions from SHAPE analyses and Addison geometric parameter. Different coordination geometries of the same metal ion in the same compartment as the function of secondary ligands are observed. © 2018 Elsevier B.V.

SASANKA MOHANTA

Chemistry

S MANDAL

N HARI

S MONDAL

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

Inorganica Chimica Acta

The work in this investigation deals with syntheses, crystal structures and ESI-MS positive of five compounds of composition [(Cu II L) 2 Na I ](ClO 4 ) (1), [(Cu II L) 2 K I ](ClO 4 ) (2), [{Cu II L(H 2 O)}Ca II (Cu II L)](ClO 4 ) 2 (3), [(Cu II L)(µ-ClO 4 )Sr II {Cu II L(MeOH) 0.6 }](ClO 4 )·1.2MeOH (4) and [(Cu II L)(µ-ClO 4 )Ba II {Cu II L(MeOH)}](ClO 4 )·MeOH (5), where H 2 L = N,N′-bis(3-ethoxysalicylidene)-1,4-butanediamine. The s-block metal ion in all of these five compounds occupies an O 8 (four phenoxo and four ethoxy) site provided by two L 2− ligands. While Na I , K I and Ca II are eight-coordinated, Sr II and Ba II are nine-coordinated due to additional coordination by an oxygen atom of a bridging perchlorate ligand. In all of 1–5, the two Cu II and M I/II are positioned in almost linear way (Cu II –M I/II –Cu II angle range = 168.24–175.39°). The geometries of the coordination environments have been understood from SHAPE analyses. A disagreement has been observed for the first time between the results of SHAPE analyses and Addison geometric parameter for the pentacoordinated environment. Some interesting structural features regarding composition, metal-ligand bond lengths and twisting of the aromatic rings have been observed. UV-Vis spectra indicates two d-d absorption of copper(II) centers in each of the five compounds. ESI-MS positive reveals the appearance of some tri/di/mononuclear ions. © 2018 Elsevier B.V.

Fulltext

Linear trinuclear copper(II)-alkali/alkaline earth metal compounds derived from a compartmental ligand

The work in this report describes the synthesis, characterization, crystal structure and magnetic properties of a two-dimensional azido-bridged Ni II Mn II heterometallic coordination polymer, [{(Ni II LMn II ) 2 (μ 1,1,3 -N 3 ) 2 }(μ 1,3 -N 3 ) 2 ] n (1), in which the H 2 L Schiff base is the [2 + 1] condensation product of 3-methoxysalicylaldehyde and 1,3-diaminopropane. In 1, two bis(μ-phenoxo)-μ 1,1,3 -azido-Ni II Mn II dinuclear units are interlinked to form a dimer-of-dinuclear moiety {Ni II Mn II } 2 ; the {Ni II Mn II } 2 structural units are further interlinked with each other by μ 1,3 -azido ligands to form a layered coordination polymer. Upon cooling, the χ M T product slowly decreases from 300 K to about 100 K, then increases abruptly from 3.74 cm 3 K mol -1 at 100 K to 113.2 cm 3 K mol -1 at 30 K, indicating a ferrimagnetic behaviour; a three-dimensional magnetic order below 37 K was determined by the divergence in the ZFC-FC measurements and ac measurements, in which the peak temperature 35 K in the in-phase at different frequencies suggests that the Curie temperature is 35 K, whereas the out-of-phase is somewhat frequency dependent, due to the glassy magnet behaviour. The title compound is among the rare examples of metallo-organic systems having a magnetic ordering Curie temperature above 30 K. Other interesting aspects in 1 regarding magnetic properties and structural features are discussed. © 2017 The Royal Society of Chemistry.

Dalton Transactions

A nickel(II)-manganese(II)-azido layered coordination polymer showing a three-dimensional ferrimagnetic order at 35 K

The work in this report presents syntheses, characterization, crystal structures and steady state and time resolved photophysical properties of four compounds of composition [Zn II 3 L 1 2 (N 3 ) 4 ] (1), [Cd II 3 L 2 2 (N 3 ) 4 ] n (2), [Zn II 2 L 2 (N 3 ) 3 ] n (3) and [Cd II 2 L 1 (N 3 ) 3 ] n (4), where HL 1 and HL 2 are the Schiff base ligands, obtained on 1:1 condensation of 3-ethoxysalicylaldehyde (for HL 1 )/3-methoxysalicylaldehyde (for HL 2 ) and N,N,2,2-tetramethyl-1,3-propanediamine. Compound 1 is a discrete trizinc(II) system, while the other three compounds are one-dimensional coordination polymers, where the building units are, respectively, tricadmium(II), dizinc(II) and dicadmium(II) moieties. The nuclearities of the cores in the Zn II –azido compound from HL 1 and the Cd II –azido compound from HL 2 are similar (1 and 2 are trinuclear) and, similarly, the Zn II –azido compound from HL 2 and the Cd II –azido compound from HL 1 are similar (3 and 4 are dinuclear), revealing an unusual structural resemblance of two metal ions of two different rows in the periodic table as the function of slight change in the ligand periphery (OEt in HL 1 , OMe in HL 2 ). The steady state/time-resolved photophysical properties reveal that cadmium(II) enhances slightly but zinc(II) enhances appreciably the fluorescence of the Schiff base ligands HL 1 and HL 2 . It has been found that both HL 1 and HL 2 are fluorogenic sensors of zinc(II). © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim

ChemistrySelect

Syntheses, Crystal Structures and Photophysical Aspects of Discrete and Polymeric Azido-Bridged Zinc(II) and Cadmium(II) Complexes: Sensing Properties and Structural Resemblance

This report describes the syntheses, crystal structures, electrospray ionisation mass spectra, catechol oxidase activity and magnetic properties of a tetracopper(ii) cluster [CuII4L2(μ3-OH)2(NCO)4]·2H2O (1) and a one-dimensional (1D) coordination polymer [{{CuII2L(μ1,1-N3)}2(μ1,1-N3)2}(μ1,3-N3)2]n (2) derived from a Schiff base ligand (HL; 1:2 condensation product of 4-ethyl-2,6-diformylphenol and 3-morpholinopropylamine). Compound 1 may be considered a dimer of two μ-phenoxo-μ3-hydroxido dicopper(ii) units, where the dimerisation takes place through the two μ3-hydroxido moieties. Compound 2 is a μ-phenoxo-μ1,1-azido dicopper(ii)-based 1D polymer, where the dicopper(ii) units are interlinked by two end-on azide bridges to form a dimer of dinuclear-type tetracopper(ii) moieties, which, in turn, are self-assembled by end-to-end azide bridges. Magnetic investigations reveal a strong antiferromagnetic interaction in the dicopper(ii) basic unit in both cases, with J values of-382 cm-1 for 1 and-220 cm-1 for 2. Both compounds have been found to be functional models for catechol oxidase activity in N,N-dimethylformamide (DMF) and acetonitrile, with Kcat values around 15 h-1 for 1 and 13 h-1 for 2. Interestingly, compound 2 is a unique example in which a dimer of a dinuclear metal unit is the node for a versatile and well-explored linker, azide, to generate a coordination polymer. It is also interesting that a coordination polymer, 2, has been identified as the functional model of catechol oxidase activity. © 2017 The Royal Society of Chemistry.

New Journal of Chemistry

Syntheses, crystal structures, magnetochemistry and catechol oxidase activity of a tetracopper(II) compound and a new type of dicopper(II)-based 1D coordination polymer

The work in this paper deals with five new complexes of composition [Cu II (MeCN)L(U VI O 2 )(NO 3 ) 2 ] MeCN (1), [(Cu II L) 3 Cd II ](ClO 4 ) 2 (2) and [(Cu II L) 2 M II (μ 1,5 -dicyanamide) 2 ] n (M = Co (3), M = Ni (4) and M = Zn (5)) derived from a single-compartment Schiff base ligand H 2 L, which is the [2 + 1] condensation product of salicylaldehyde and 1,4-diaminobutane. Single crystal X-ray structures of all the five complexes have been determined. Compound 1 is a diphenoxo-bridged Cu II (U VI O 2 ) system, compound 2 is a star-shaped tetranuclear system where the cadmium(II) center is encapsulated in between three [Cu II L] moieties and the three isomorphous compounds 3-5 are trinuclear Cu II M II Cu II -based (M = Co, Ni, Zn) two-dimensional, square-grid systems where the trinuclear units are bridged by μ 1,5 -dicyanamide ligands. In addition to the exploration of much less investigated Schiff base ligand family having four carbon atoms between the two imine nitrogen atoms, the types of structures presented here either have some novelties or are new examples and therefore deserves importance. The d-d spectra of copper(II)-diamagnetic metal ion complexes (1, 2 and 5) and the corresponding mononuclear copper(II) compound have been recorded with the aim to shed light on the correlation of d-d band position with the displacement of copper(II) from the least-squares basal plane, revealing excellent correlation. © 2014 Elsevier B.V. All rights reserved.

Dinuclear, star-shaped tetranuclear and trinuclear-based two-dimensional metal complexes derived from a less investigated Schiff base ligand: Syntheses, crystal structures and spectroscopic correlation

Dinuclear, dimer-of-dinuclear and new type of polymeric metal complexes of copper(II)â€“zinc(II)/cadmium(II) derived from a less explored compartmental ligand

Journal	Data powered by TypesetInorganica Chimica Acta
Publisher	Data powered by TypesetElsevier S.A.
ISSN	0020-1693
Open Access	No