Brajagopal Samanta

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.

Synthesis, Structure and Fluorescence Properties of a Trinuclear Zn(II) Complex with N,N,O-donor Schiff Base Ligands and Bridging Acetates

A new centrosymmetric trinuclear Zn(II) complex [Zn3L2(CH3COO)4] (1) has been synthesized by the reaction of Zn(CH3COO)2 · 2H2O with a tridentate N,N,O-donor Schiff base ligand HL [C5H4NC(CH3)=NC6H4(OH)] and systematically characterized by elemental analysis, FT-IR, UV/Vis and thermal methods. Single crystal X-ray structure analysis reveals that three Zn(II) centers are in two different coordination environments. Two terminal Zn(II) centers adopt a distorted squarepyramidal geometry leaving the central Zn(II) in a distorted octahedral environment. Two adjacent metal centers are connected through single μ2-phenolato as well as double μ-acetato-O,O´ syn-syn bridges. Fluorescence properties of the complex as compared to the ligand indicate that the former can serve as a potential photoactive material. Graphical Abstract Synthesis, Structure and Fluorescence Properties of a Trinuclear Zn(II) Complex with N,N,O-donor Schiff Base Ligands and Bridging Acetates

A New Polymeric Barium-Iron (III) Complex with Chain and Large Ring Structure

The compound {[Ba6(Phen)12(CF3COO)6{Fe(CN)6}2(H2O)8]·6 H2O}n (1) (Phen = 1,10-phenanthroline) has been synthesized and structurally characterized. In the crystal structure, the two consecutive Ba centres are bridged through trifluoroacetate groups and also via cyano groups of [Fe(CN)6]3− and form the zigzag chain resulting the formation of 24-membered ring structure. The Ba-centres are 8-fold coordinated with distorted cubic geometry. Six H2O molecules per asymmetric unit remain in the structure without any direct interaction with the metal atoms but they act in hydrogen bond formation.

Synthesis, Characterisation and Crystal Structure of a Copper(II) Dichromate Complex with the N,N’-Bis(2-pyridylmethylene)butane- 1,4-diamine Schiff Base Ligand

The new complex Cu[L1]Cr2O7has been synthesised with the N,N′-bis(2-pyridylmethylene) butane-1,4-diamine Schiff base L1, [NC5H4CH=N(CH2)4N=CHC5H4N], and characterised with elemental analyses and different spectroscopic and electrochemical studies. The structure of the new complex has been established by single crystal X-ray diffraction. The complex crystallises in the monoclinic system with space group P21/c having cell parameters a = 14.7(5), b = 9.22(2), c = 16.2(5) Å , β = 116.9(1)°, and Z = 4. The Cr2O72− unit is bonded through one terminal oxygen donor end to the central Cu(II) chelated by the Schiff base ligand.

Synthesis, Characterisation, Structure, and Magnetic Properties of [Ni{H2NCH(CH3)CH2NH2}3][Fe(CN)5NO]·H2O

The complex [Ni(pn)3][Fe(CN)5NO]·H2O (1) was synthesised by the reaction of [Ni(pn)3]Cl2 (pn = racemic propane-1,2-diamine) with Na2[Fe(CN)5NO]·2H2O in aqueous solution and has been charaterised by IR and Mössbauer spectroscopy and magnetic studies. Single crystal structure analysis revealed octahedrally coordinate cations [Ni(pn)3]2+ and anions [Fe(CN)5NO]2−.