Syntheses, X-ray crystal structures and spectroscopic characterization of rare μ-di-σ pyrazole based bridging keto carbonyl complexes derived from Cd(II) salts. (8th January 2015)

• Record Type: Journal Article
• Authors: Das, Kinsuk; Konar, Saugata; Pal, Pampi; Jana, Atanu; Chatterjee, Sudipta; Mukhopadhyay, Subrata
• Is Part Of: Polyhedron. Volume 85(2015)
• Page Start: 172
• Page End: 180
• Publication Date: 2015-01-08
• Subjects: Pyrazole derived ligands -- Cadmium(II) complexes -- X-ray crystal structure -- Supramolecular interactions -- Photoluminescence; Chemistry, Inorganic -- Periodicals; Chimie inorganique -- Périodiques; Organometaalverbindingen; Anorganische chemie; 546.05
• DOI: 10.1016/j.poly.2014.08.043
• Languages: English
• ISSNs: 0277-5387

Abstract

Abstract : Graphical abstract: Three new rare keto oxygen bridged Cd(II) complexes have been prepared from the pyrazole based ligands N-PzOPyH and PzOPyH, and Cd(II) metal precursors. They have been synthesized and characterized both structurally and spectroscopically. These rare keto bridged Cd(II) complexes are stabilised by supramolecular interactions, like π⋯π, C–H⋯π and H-bonding interactions. Abstract: The pyrazole based ligands (E)-2-(3, 5-dimethyl-1H-pyrazol-1-yl)-N′-(pyridin-2-ylmethylene acetohydrazide (N-PzOPyH) and (E)-5-methyl-N′-(pyridin-2-ylmethylene)-1H-pyrazole-3-carbo hydrazide (PzOPyH), a 1:1 condensation product of 2-(3, 5-dimethyl-1H-pyrazol-1-yl)aceto hydrazide and 5-methylpyrazole-3-carbohydrazide with pyridine-2-carbaldehyde respectively, and their keto oxygen bridged Cd(II) complexes [Cd2 (N-PzOPy)2 (H2 O)4 ](ClO4 )4 (1 ), [Cd2 (PzOPy)2 (H2 O)4 ](ClO4 )4 (2 ) and [Cd2 (PzOPy)2 (NO3 )4 ] (3 )] are reported. They have been characterized structurally and spectroscopically. The potential tetradentate NONN-donor ligands N-PzOPyH and PzOPyH are engaged in the coordination around the cadmium(II) center through the nitrogen atoms of pyrazole, azomethine and pyridine and the ketonic oxygen atom of the carbohydrazide group to form complexes1, 2 and3, respectively. These ligands span themselves in the equatorial plane and the pentagonal bipyramidal geometry is completed around the metal centres (with an N3 O4 chromophore) with two apical water molecules (for1 and2 ) and with two nitrate ions (for3 ). These keto bridged Cd(II) complexes are further stabilised by supramolecular interactions, like π⋯π, C–H⋯π and H-bonding interactions.