Synthesis, Optical, Electrochemical, and Theoretical Studies of Dipolar Ruthenium Alkynyl Complexes with Oligo(phenylenevinylene) Bridges1. Issue 7 (17th June 2016)

• Record Type: Journal Article
• Authors: Zhang, Huihua; Morshedi, Mahbod; Kodikara, Mahesh S.; Moxey, Graeme J.; Wang, Genmiao; Wang, Huan; Quintana, Cristóbal; Stranger, Rob; Zhang, Chi; Cifuentes, Marie P.; Humphrey, Mark G.
• Is Part Of: ChemPlusChem. Volume 81:Issue 7(2016)
• Page Start: 613
• Page End: 620
• Publication Date: 2016-06-17
• Subjects: computational chemistry -- electrochemistry -- nonlinear optics -- organometallic chemistry -- transition metals; Chemistry -- Periodicals; 540.5
• DOI: 10.1002/cplu.201600203
• Languages: English
• ISSNs: 2192-6506

Abstract

Abstract: The syntheses of oligo( p ‐phenylenevinylene)s (OPVs) end‐functionalized with a ligated ruthenium alkynyl unit as a donor and a nitro as acceptor, namely trans ‐[Ru{C≡C‐1‐C6 H4 ‐4‐( E )‐CH=CH‐1‐C6 H2 ‐2, 5‐Et2 ‐4‐( E )‐CH=CH‐1‐C6 H2 ‐2, 5‐Et2 ‐4‐( E )‐CH=CH‐1‐C6 H4 ‐4‐NO2 }Cl(dppe)2 ] (Ru4 ), trans ‐[Ru{C≡C‐1‐C6 H4 ‐4‐( E )‐CH=CH‐1‐C6 H2 ‐2, 5‐Et2 ‐4‐( E )‐CH=CH‐1‐C6 H2 ‐2, 5‐Et2 ‐4‐( E )‐CH=CH‐1‐C6 H2 ‐2, 5‐( n ‐hexyl)2 ‐4‐( E )‐CH=CH‐1‐C6 H2 ‐2, 5‐( n ‐hexyl)2 ‐4‐( E )‐CH=CH‐1‐C6 H4 ‐4‐NO2 }Cl(dppe)2 ] (Ru6 ), and trans ‐[Ru{C≡C‐1‐C6 H4 ‐4‐( E )‐CH=CH‐1‐C6 H2 ‐2, 5‐Et2 ‐4‐( E )‐CH=CH‐1‐C6 H2 ‐2, 5‐Et2 ‐4‐( E )‐CH=CH‐1‐C6 H2 ‐2, 5‐( n ‐hexyl)2 ‐4‐( E )‐CH=CH‐1‐C6 H2 ‐2, 5‐( n ‐hexyl)2 ‐4‐( E )‐CH=CH‐1‐C6 H2 ‐2, 5‐(2‐ethyl‐ n ‐hexyl)2 ‐4‐( E )‐CH=CH‐1‐C6 H2 ‐2, 5‐(2‐ethyl‐ n ‐hexyl)2 ‐4‐( E )‐CH=CH‐1‐C6 H4 ‐4‐NO2 }Cl(dppe)2 ] (Ru8 ), are reported, together with those of precursor alkynes. Their electrochemical properties were assessed by cyclic voltammetry (CV), their linear optical and quadratic nonlinear optical (NLO) properties assayed by UV/Vis‐NIR spectroscopy and hyper‐Rayleigh scattering studies at 1064 nm, respectively, and their linear optical properties in the formally Ru III state examined by UV/Vis‐NIR spectroelectrochemistry. Computational studies employing time‐dependent density functional theory were undertaken on model complexes to rationalize the optical observations. Abstract : Crossing bridges : For end‐functionalized oligo( p ‐phenylenevinylene)s (OPVs) with a donor‐ligated ruthenium centre and acceptor nitro group (see figure), oxidation potentials and wavelength of the UV/Vis λ max band plateau and quadratic nonlinearities are maximized around the complex with a tri(phenylenevinylene) unit. Computational studies suggest that intra‐OPV rotations result in the experimentally observed, relatively invariant properties for the higher OPV examples.