A rare ferromagnetically coupled asymmetric doubly azido bridged copper(II) dimer with an N, N, O donor Schiff base

• Published in: Polyhedron Vol. 26; no. 7; pp. 1357 - 1363
• Main Authors: Shit, Shyamapada, Talukder, Pritha, Chakraborty, Joy, Pilet, Guillaume, Salah El Fallah, M., Ribas, Joan, Mitra, Samiran
• Format: Journal Article
• Language: English
• Published: OXFORD Elsevier Ltd 01.05.2007; Elsevier
• Subjects: Chemistry; Chemistry, Inorganic & Nuclear; Copper(II); Crystal structure; Crystallography; Doubly azido bridge (EE); Ferromagnetic; Physical Sciences; Schiff base; Science & Technology; Schiff base; Doubly azido bridge (EE); Ferromagnetic; Copper(II); Crystal structure; CRYSTAL-STRUCTURE; NICKEL(II) COMPLEXES; CU(II) COMPLEXES; doubly azido bridge (EE); CHAIN; CADMIUM(II); MAGNETOSTRUCTURAL CORRELATIONS; ferromagnetic; LIGANDS; ANTIFERROMAGNETIC INTERACTIONS; crystal structure; copper(II); MAGNETIC-PROPERTIES; COUNTERANION
• ISSN: 0277-5387; 1873-3719
• DOI: 10.1016/j.poly.2006.11.013

A new end-to-end (EE) doubly azido bridged centrosymmetric dinuclear complex has been synthesized and characterized with elemental and spectroscopic techniques. In the complex, each copper atom is in a distorted square pyramidal geometry with a CuN 4O chromophore. Temperature dependent magnetic susceptibility, fitted using the Bleaney–Bowers expression indicates a ferromagnetic interaction through the double azido bridges connecting the adjacent copper(II) centers. A new end-to-end (EE) doubly azido bridged dinuclear complex [Cu 2L 2(μ 1,3-N 3) 2] ( 1) [where L = ( E)-4-(2-(dimethylamino)ethylimino)-1,1,1-trifluoropentan-2-one)] has been synthesized and characterized by elemental and spectroscopic techniques. Single crystal X-ray diffraction analysis reveals that the dimeric complex possesses a center of inversion. Each copper atom in 1 is in a distorted square pyramidal geometry with a CuN 4O chromophore as revealed from the τ value, 0.19. The four basal positions are occupied by two imine N and one keto O atom of the Schiff base and one N atom from the azide anion. Another N atom from a coordinated azide occupies the apical position. Temperature dependent magnetic susceptibility of 1 was fitted using the Bleaney–Bowers expression which led to the parameters J = 13.6 cm −1 and R = 3.4 × 10 −5. It indicates a ferromagnetic interaction through the double azido bridges connecting the individual copper Schiff base units.