A novel triply bridged dinuclear four-coordinate copper(I) complex with sterically bulky bis(dicyclohexylphosphino)methane ligand

Abstract

A novel triply bridged dinuclear four-coordinate Copper(I) Complex with sterically bulky bis(dicyclohexylphosphino)methane ligand * E-mail: wf_fu@yahoo.com.cn Abstract: A novel triply bridged dinuclear copper(I) complex: Cu 2 (µ-paa)(µ-dcpm) 2 (BF 4 ) 2 ·2CH 2 Cl 2 [ paa = pyridine-2-carbaldehyde azine (C 12 H 10 N 4 ) and dcpm = bis(dicyclohexylphosphino)methane(C 25 H 46 P 2 ) ] has been synthesized and structurally characterized. Crystallographic studies of the complex showed that two copper(I) ions were bridged by one paa ligand and two dcpm ligands. The paa ligand adopted the Z configuration at the partially double N-N bond and the two copper ions have distorted tetrahedral coordination geometry.Because of the steric effect of dcpm, the pyridine rings of the paa ligand are obviously not on the same plane (the dihedral angle is 43.61 0 ). The interaction between neighboring ligands results in a N-N bond length (1.374(7) Å) contraction. The UV-vis spectra of the complex exhibited intense high-energy absorptions at λ max < 340 nm and broad visible bands in a range of 380-550 nm, ascribed to intraligand (IL π-π*) transitions and metal-to-ligand charge-transfer (MLCT) transitions, respectively. Interestingly, the absorbtion peaks varied regularly with the solvent polarity. Although the complex has a rigid structure with the copper ions held firmly by triply bridged ligands, the emission and excitation spectra revealed that the complex exhibits weak fluorescence. Warsaw and Springer-Verlag Berlin Heidelberg. © Versita

Inhibition effect of E and Z conformations of 2-pyridinealdazine on mild steel corrosion in phosphoric acid

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Complex Spectroscopy Studies of Nifedipine Photodegradation

“…The UV-VIS spectrum of NIF (black curve in Figure 1a) presents a band of high absorbance at 240 nm, with a shoulder at 272 nm, and another band at 340 nm. Bands at 240 nm (5.2 eV), 272 nm (4.6 eV) and 340 nm (3.6 eV) were associated with the electronic transitions of the chromophore groups -COOCH 3 [28] and -NO 2 [29] and a heterocycle with six atoms [30]. The ratio between the absorbances of the bands at 240 nm, 270 nm and 340 nm is 3.6:2:1.…”