Formation of three photoluminescent dinuclear cadmium(II) complexes with Cd2O2 cores

Condensation of N,N-dimethyl-1,3-diaminpropane with salicylaldehyde, 3-methoxysalicylaldehyde and 3-ethoxysalicylaldehyde produces three Schiff bases, HL1 [2-(3-(dimethylamino)propylimino)methyl)methoxyphenol], HL2 [2-(3-(dimethylamino)propylimino)methyl)-6-methoxyphenol], and HL3 [2-(3-(dimethylamino)propylimino)methyl)-6-ethoxyphenol], respectively. Addition of cadmium(II) chloride to the methanol solution of the tridentate Schiff base, HL1, produces phenoxo-bridged dinuclear cadmium(II) complex, [Cd2(L1)2(Cl)2] (1). Similarly, addition of cadmium(II) nitrate to the methanol solution of the tetradentate Schiff base, HL3, produces phenoxo-bridged dinuclear cadmium(II) complex, [Cd2(L3)2(NO3)2] (3). On the other hand, [Cd(L2)2Cd(NCO)2] (2), is produced by the addition of cadmium(II) perchlorate into the methanol solution of tetradentate Schiff base, HL2 followed by the addition of sodium cyanate. Structures of the complexes have been confirmed by single crystal X-ray diffraction studies. All complexes are dinuclear with Cd2O2 cores. Complex 1 contains square pyramidal cadmium(II) centres, whereas complexes 2 and 3 contain octahedral cadmium(II) centres. All three complexes show fluorescence.

Three new photo-luminescent dinuclear phenoxo-bridged cadmium(II) complexes have been synthesized and characterized by single crystal X-ray analysis. Tridentate and tetradentate ligands have been used as chelating ligands in preparing complexes. Structures of the complexes were varied with the variation in the denticity of chelating ligands.Figure optionsDownload as PowerPoint slide