Heterometallic Cu(I)/Ru(II) halide and pseudohalide hybrid complexes composed of coordination and organometallic sites: Synthesis, spectroscopic characterization, electrochemical and luminescence properties

• Published in: Polyhedron 2017-05, Vol.128, p.112-120
• Main Authors: Pawal, S.B., Lolage, S.R., Chavan, S.S.
• Format: Article
• Language: English
• Subjects: Cyclic voltammetry; Heterometallic complexes; Photoluminescence; Solvatochromism; TGA
• ISSN: 0277-5387
• DOI: 10.1016/j.poly.2017.03.001

A new series of heterometallic halide/pseudohalide hybrid complexes of the type [Cu(L1)NC5H4–CC–C6H3–1,3-{CC-trans-RuCl(dppe)2}2X] (1a–d) and [Cu(L2)NC5H4–CC–C6H3–1,3-{CC-trans-RuCl(dppe)2}2X] (2a–d) have been prepared and characterized (where L1=4-methoxy-N-(2-pyridylmethylene)phenylamine and L2=4-nitro-N-(2-pyridylmethylene)phenylamine; X=Cl, I, N3 and SCN). Quasireversible redox behavior is accounted for all complexes corresponding to Cu(I)/Cu(II) and Ru(II)/Ru(III) couple. Room temperature luminescence is observed for all complexes which indicate that the emission wavelength is finely tuned by variation of the substituent group as well as quenching ability of halides and pseudohalides in the complexes. The excited state of 1a–d and 2a–d are stabilized and red shifted in their emission wavelength with increasing polarity of the solvents. [Display omitted] A new series of heterometallic halide/pseudohalide hybrid complexes of the type [Cu(L1)NC5H4–CC–C6H3–1,3-{CC-trans-RuCl(dppe)2}2X] (1a–d) and [Cu(L2)NC5H4–CC–C6H3–1,3-{CC-trans-RuCl(dppe)2}2X] (2a–d) have been prepared by the reaction of [NC5H4–CC–C6H3–1,3-{CC-trans-RuCl(dppe)2}2] (1) with copper(I) salts in presence of L1 and L2 (where L1=4-methoxy-N-(2-pyridylmethylene) phenylamine and L2=4-nitro-N-(2-pyridylmethylene)phenylamine; X=Cl, I, N3, and NCS) in CH2Cl2/MeOH mixture. Thermal stability of 1a–d and 2a–d has been investigated by using thermogravimetric analysis (TGA). The electrochemical behaviour of 1a–d and 2a–d reveals that all complexes display a quasireversible redox behaviour corresponding to Cu(I)/Cu(II) and Ru(II)/Ru(III) couples. The room temperature luminescence is observed for all complexes in dichloromethane solution indicating that the emission wavelength is finely tuned by the variation of the substituent group on iminopyridine ligand and quenching ability of halides and pseudohalides in the complexes. Further, the excited state of 1a–d and 2a–d are stabilized and red shifted in their emission wavelength with increasing polarity of the solvents.