Pritha Talukder

A novel doubly phenoxo-bridged Cu(II) trimer: synthesis, crystal structure and low-temperature magnetic behaviour

A novel doubly phenoxo-bridged Cu(II) trimeric complex, [trinuclear diperchlorato {2,2′-[1,3-propanediylbis (nitriloethylidyne)]bisphenolato}-tricopper] has been synthesised with a tetradentate Schiff base ligand and characterised by IR, electronic spectra, X-ray structure and variable temperature magnetic moments. The Cu1 centre has square pyramidal geometry where as the Cu2 centre achieves square planar geometry. The dihedral angle between the two planes, Cu1 – O1 – O2 and Cu2 – O1 – O2 is 26.50°.

Two New Quadridentate Schiff Base Complexes of Nickel(II) and Cobalt(III): Synthesis, Structure and Spectral Characterisation

Two novel quadridentate Schiff base complexes, [NiIILH](ClO4)2・H2O (1) and [CoIIIL]- (ClO4)2・H2O (2) [LH, a Schiff base ligand: Ph(OH)C(Me)=NCH2CH2N(CH2CH2NH2)2] have been synthesised and characterised by elemental analyses, spectroscopic and electrochemical studies. The structures of both have been unequivocally established from single crystal X-ray diffraction studies. 1 and 2 crystallise in the monoclinic space group P21/n having cell parameters a = 8.536(1), b = 13.832(4), c = 18.194(2) Å , β = 100.00(10)°, Z = 4 for 1, and a = 10.819(5), b = 14.301(2), c=14.224(1) Å , β =97.04(2)°, Z =4 for 2. The complexes expose a square planar geometry around the metal centers chelated with three different types of nitrogen donor centers of the ligand.

Square Planar Complexes of Cu(II) with an N2O Donor Set of a New Schiff Base Ligand: Synthesis and Structural Aspects

The title compounds, [Cu(C16H23N2O)SCN] (1) and [Cu(C16H23N2O)N3] (2), containing a tridentate Schiff base ligand, which is the 1:1 condensation product of benzoylacetone and 2- diethylaminoethylamine, have been synthesised and their crystal structures determined. The structure of 1 is based on a four coordinate copper centre with square-planar geometry formed by the N2O donor set of the Schiff base and an N atom of the thiocyanate anion. A similar arrangement occurs in 2 with the N2O donor set of the Schiff base and an N atom of the azide anion. The Cu-N and Cu-O distances are 1.924(8), 2.073(8), 1.927(9) and 1.910(6)Å , for 1 and 1.960(4), 2.050(4), 1.935(4) and 1.907(3) for 2, respectively.

A new one-dimensional coordination polymer [Co(CCl3COO) 2(CH3OH)2(μ-4,4′-bipy)]n: Synthesis and structural aspects

A new one-dimensional coordination polymer [Co(CCl3COO)2(CH3OH)2(μ-4,4’-bipy)]n (1), has been synthesised and its crystal structure determined by single-crystal X-ray diffraction. The structure consists of a one-dimensional linear chain of cobalt(II) centres linked by bridging 4,4’-bipyridine units. The Co(II) ion lies at an inversion centre forming an elongated octahedral coordination sphere. There is an intramolecular hydrogen bond [2.02(5) Å ] between a trichloroacetate oxygen and a methanolic hydrogen forming a planar six-membered ring.