The work in this report deals with seven compounds of composition {[Cu II(dmpn)2]3[FeIII(CN) 6]2·6H2O}n (1), {[Cu II(dmpn)2]3[CoIII(CN) 6]2·6H2O}n (2), {[Cu II(dmpn)2]3[CrIII(CN) 6]2·4H2O}n (3), {[Cu II(dmpn)][NiII(CN)4]·H 2O}n (4), [{CuII(dmpn)2Cl}{Cu II(dmpn)2(H2O)}][AgI(CN) 2]Cl2 (5), [(CuII(dmpn) 2(dicyanamide)2] (6) and [(NiII(dmpn) 2(dicyanamide)2] (7), where dmpn = 2,2-dimethyl-1,3- diaminopropane. Syntheses, characterization and crystal structures of 1-7 along with variable-temperature (2-300 K) magnetic properties of 1 and 3 are described. Compounds 1-4 are cyanide-bridged two-dimensional coordination polymers. Twelve metal-membered ring is formed in 1-3, while both four and eight metal-membered rings are formed in 4. On the other hand, dicyanoargentate(I) in 5 is noncoordinated and dicyanamide in 6 and 7 behaves as monodentate terminal ligand. The coordination polymers in 1-4 and the discrete systems in 5-7 are self-assembled by hydrogen bonding interactions to generate overall three-dimensional supramolecular topologies. A novel structural aspect, two-dimensional network containing both four and eight metal-membered rings, has been observed in the copper(II)-tetracyanonickelate(II) compound 4. Magnetic studies reveal ferromagnetic interaction between CuII and Cr III in 3. In addition, spin-orbit coupling of low-spin Fe III or weak antiferromagnetic interaction along with intermolecular antiferromagnetic interactions which exist between CuII and Fe III are present in 1. © 2014 Elsevier Ltd. All rights reserved.

SASANKA MOHANTA

Chemistry

A BISWAS

A JANA

S SARKAR

J A K HOWARD

N ALIAGA-ALCALDE

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

Polyhedron

This paper presents syntheses, characterization, crystal structures and magnetic properties of two diphenoxo-bridged heterodinuclear Cu IIMnII/CuIIFeII compounds [Cu IIL1MnII(H2O)3](ClO 4)2 (1) and [CuIIL1Fe II(H2O)3](ClO4)2 (2) and two tetranuclear CuII3MnII/CuII 3FeII compounds [{CuIIL2Mn II(H2O)(MeOH)2}(CuIIL 2)2](ClO4)2·MeOH (3) and [{CuIIL2FeII(H2O)(MeOH) 2}(CuIIL2)2](ClO4) 2·MeOH (4) derived from two 3-methoxysalicylaldehyde-diamine Schiff base compartmental ligands H2L1 and H 2L2, in which the diamine counterpart comes from 1,3-diaminopropane and o-phenylenediamine, respectively. The two compounds 1 and 2 crystallize in the same space group (monoclinic P21/n) with practically identical unit cell parameters and are isomorphous. Similarly, the two compounds 3 and 4 crystallize in the same space group (monoclinic P2 1/c) with practically identical unit cell parameters and are isomorphous. The tetranuclear [{CuIIL2M II(H2O)(MeOH)2}(CuIIL 2)2]2+ dication in 3 (M = Mn) and 4 (M = Fe) is a self-assembly of one diphenoxo-bridged dinuclear [CuIIL 2MII(H2O)(MeOH)2]2+ dication and two mononuclear [CuIIL2] units. One mononuclear unit is self-assembled with the dinuclear unit by four bifurcated water⋯phenoxo/methoxy (O-H⋯O) hydrogen bonds and three π⋯π stacking interactions, while the second mononuclear unit is interlinked with the dinuclear unit by one methanol⋯phenoxo (O-H⋯O) hydrogen bond only. Clearly, compounds 3 and 4 are [2 × 1 + 1 × 2] cocrystals of one dinuclear and two mononuclear units. Variable-temperature magnetic susceptibility measurements of all the four compounds have been carried out, revealing moderate antiferromagnetic interaction between the copper(ii) and manganese(ii)/iron(ii) in the dinuclear cores with J values (H = -2JS1S2) -29.1, -36.9, -15.9 and -20.2 cm-1, respectively. The magnetic properties are in line with those of previous related examples. Unique features in the structures of 1-4 have been discussed. © 2013 The Royal Society of Chemistry.

CrystEngComm

More surprising differences between two closely similar compartmental ligand families and another dinuclear synthon to stabilize dinuclear-mononuclear cocrystals

The syntheses, characterization and crystal structures of four copper(ii)/nickel(ii)⋯uranyl(vi) self-assemblies of composition [{Ni IIL1}2·{(UVIO 2)(NO3)2(H2O)2}] (1), [{CuIIL2}2·{(UVIO 2)(NO3)2(H2O)2}] ·0.68H2O (2), [{NiIIL2} 2·{(UVIO2)(NO3) 2(H2O)2}] (3) and [{CuIIL 3}·{(UVIO2)(NO3) 2(H2O)2}]n (4) are described in this investigation (H2L1, H2L2 and H2L3 are the Schiff base ligands obtained on condensing 3-ethoxysalicylaldehyde with ethylenediamine, o-phenylenediamine and trans-1,2-diaminocyclohexane, respectively). Compounds 1 and 4 crystallized in the monoclinic P21/n and C2/c space groups, respectively, while compounds 2 and 3 crystallized in the triclinic space group P1. Two water molecules of the [(UVIO2)(NO3) 2(H2O)2] moiety in 1-4, have a linear H 2O-U-OH2 arrangement. Each of these two water molecules in 1-3 interacts with the O(phenoxo)2O(ethoxy)2 compartment of a mononuclear copper(ii) or nickel(ii) moiety due to the formation of bifurcated hydrogen bonds between each of the two water hydrogen atoms and a pair of one phenoxo and one ethoxy oxygen atoms resulting in the interlinking of the two mononuclear 3d units by the [(UVIO2)(NO 3)2(H2O)2] synthon and therefore these three compounds may be considered as supramolecular dimers. Compounds 1-3 are also two component [1 × 2 + 1 × 1] co-crystals consisting of two mononuclear copper(ii) or nickel(ii) units and one [(UVIO 2)(NO3)2(H2O)2] moiety. On the other hand, in 4, two water molecules, from two different [(U VIO2)(NO3)2(H2O) 2] moieties, interact with one O(phenoxo)2O(ethoxy) 2 compartment resulting in the formation of a self-assembled one-dimensional topology. Again, since one mononuclear copper(ii) unit and one [(UVIO2)(NO3)2(H2O) 2] moiety exist in a single crystal in 4, this compound is a two component [1 × 1 + 1 × 1] co-crystal. The outcomes of the present study utilize [(UVIO2)(NO3)2(H 2O)2] synthon to derive 3d⋯5f co-crystals, provide the first observation of the interaction of two water molecules with one O(phenoxo)2O(ethoxy)2 compartment, demonstrate the formation of supramolecular dimers and show the first example of a one-dimensional self-assembly resulting from water⋯O4 compartment hydrogen bonds, and the first example of [1 × 2 + 1 × 1] co-crystals in 3-ethoxysalicylaldehyde-diamine ligand system. © 2011 The Royal Society of Chemistry.

Bis(nitrate)diaquauranyl(vi) synthon to generate [1 Ã— 2 + 1 Ã— 1] and [1 Ã— 1 + 1 Ã— 1] co-crystalized 3dâ‹¯5f self-assemblies

The work in this paper aims to portray a complete structural, magnetic, and theoretical description of two original end-to-end (EE) mu(1,3)-azide-bridged, cyclic tetranuclear Ni(II)clusters, [{Ni-II(L-1)(mu(1,3)-N-3)(H2O)}(4)] (1) and [{Ni-II(L-2)(mu(1,3)-N-3)(H2O)}(4)] (2), where the ligands used to achieve these species, HL1 and HL2, are the tridentate Schiff base ligands obtained from [1 + 1] condensations of salicylaldehyde with 1-(2-aminoethyl)-piperidine and 4-(2-aminoethyl)-morpholine, respectively. The title compounds, 1 and 2, crystallize in a monoclinic P2(1) space group. Overall, both species can be described in a similar way; where all Ni-II centers within each molecule are hexacoordinated and bound to [L-1](-) or [L-2](-) through the phenoxo oxygen, imine nitrogen, and piperidine/morpholine nitrogen atoms of the corresponding ligand. The remaining coordination sites are satisfied by one molecule of H2O and two nitrogen atoms from N-3(-) anions. The latest act as bridges between Ni-II ions, and eventually, only four azido groups are linked to the same number of Ni-II centers resulting in the formation of cyclic Ni-4(II) systems. Interestingly, compounds 1 and 2 are the two sole examples of tetranuclear clusters generated exclusively by EE azide-bridging ligands to date. All the N(azide)-Ni-N(azide) moieties are almost linear in 1 and 2 indicating trans arrangement of the azido ligand. Variable-temperature (2-300 K) magnetic susceptibilities of 1 and 2 have been measured under magnetic fields of 0.04 T (from 2 to 30 K) and 0.7 T (from 30 to 300 K), and magneto-structural correlations have been performed. Despite the presence of both ferromagnetic and antiferromagnetic interactions in both compounds, significant differences have been observed in their magnetic behaviors directly related to the arrangement of the bridging azido ligands. Hence, compound 1 has an overall moderate antiferromagnetic behavior due to the presence of an exchange pathway with an unprecedented Ni-N center dot center dot center dot N-Ni torsion angle close to 0 degrees, meanwhile complex 2 exhibits a predominant ferromagnetic behavior, with torsion angles between 50 and 90 degrees. Density functional theory calculations have been performed to provide more insight into the magnetic nature of this new family of Ni-II-azido complexes and also to corroborate the fitting of the data.

Inorganic Chemistry

Magneto-Structural Correlation Studies and Theoretical Calculations of a Unique Family of Single End-to-End Azide-Bridged Ni-4(II) Cyclic Clusters

Syntheses, characterizations, electrochemistry and catalytic properties for styrene epoxidation of three manganese(III) compounds [MnIIIL1(H2O)(MeOH)](ClO4) (1) [MnIIIL1(N3)(H2O)]·dmf (2) [MnIIIL1(Cl)(H2O)] (3) derived from the Schiff base compartmental ligand N,N′-o-phenylenebis(3-ethoxysalicylaldimine) (H2L1) are reported. The three compounds are characterized by elemental analyses, IR, mass and UV-Vis spectra and conductance values. Single crystal X-ray structures of 1 and 2 have been determined. The structures of 1 and 2 show that these are mononuclear compounds having a salen type structure. In both structures, a dinuclear species is formed by bifurcated hydrogen bonding involving coordinated water molecule. The coordination of chloride in 3 is shown by conductance measurements. The compounds have also been characterized by UV-Vis and mass spectroscopic studies. Cyclic voltammetric and square wave voltammetric studies of the three compounds reveal that these undergo Mn(III)/Mn(II) reduction reversibly with the order of the ease of reduction as 3 &gt; 2 &gt; 1. This order has been explained proposing the composition of active species in solution. Catalytic properties for epoxidation of styrene by all the three complexes using PhIO and NaOCl as oxidant have been studied. The order of both the styrene conversion and styrene epoxidation using the three title compounds is 3 &gt; 1 &gt; 2. Again, it has been observed that more efficient conversion and epoxidation take place when PhIO is used as oxidant. © 2009 Elsevier Ltd. All rights reserved.

Syntheses, structures and electrochemistry of manganese(III) complexes derived from N,Nâ€²-o-phenylenebis(3-ethoxysalicylaldimine): Efficient catalyst for styrene epoxidation

The synthesis, characterization, and structure of a cyano-bridged two-dimensional supramolecule, [CuII(trans-chxn)2] 3[CoIII(CN)6]2·2H 2O (1; chxn = 1,2-diaminocyclohexane), have been described. The title compound crystallizes in the triclinic Pī space group with the unit cell parameters: a = 9.141(5) Å, b = 12.406(5) Å, c = 15.064(5) Å, α = 95.190(5)°, β = 94.460(5)°, γ = 109.510(5)°, V = 1593.0(12) Å3, and Z = 1. The compound contains two crystallographically different copper(II) and cobalt(III) centers. Each of the two copper(II) ions is hexacoordinated by two diamines and two bridging cyanides. Two trans cyanides of one type of hexacyanometalate link one type of copper(II) center to result in one-dimensional chain, while two pairs of trans cyanides of the second type of hexacyanometalate link both the types of copper(II) ions to result in the second dimension. There are extensive hydrogen bonding interactions within the two-dimensional cyano-bridged sheet involving the solvated water molecule, amine groups, and cyanide nitrogens. © 2008 Springer Science+Business Media, LLC.

Journal of Chemical Crystallography

Synthesis, characterization, and structure of a cyano-bridged two-dimensional CuIICoIII coordination polymer derived from trans-1,2-diaminocyclohexane as blocking ligand

Discrete systems and two-dimensional coordination polymers containing potentially multidentate and bridging inorganic anions: Observation of a new type of two-dimensional topology

Journal	Data powered by TypesetPolyhedron
Publisher	Data powered by TypesetElsevier Ltd
ISSN	0277-5387
Open Access	No