Syntheses and Photophysics of Luminescent Mono- And Dinuclear Rhenium Complexes Containing Functional Ligands

Download or read book Syntheses and Photophysics of Luminescent Mono- And Dinuclear Rhenium Complexes Containing Functional Ligands written by Man-Chung Wong and published by Open Dissertation Press. This book was released on 2017-01-27 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation, "Syntheses and Photophysics of Luminescent Mono- and Dinuclear Rhenium Complexes Containing Functional Ligands" by Man-chung, Wong, 黃文忠, was obtained from The University of Hong Kong (Pokfulam, Hong Kong) and is being sold pursuant to Creative Commons: Attribution 3.0 Hong Kong License. The content of this dissertation has not been altered in any way. We have altered the formatting in order to facilitate the ease of printing and reading of the dissertation. All rights not granted by the above license are retained by the author. Abstract: Abstract of thesis entitled "SYNTHESES AND PHOTOPHYSICS OF LUMINESCENT MONO- AND DINUCLEAR RHENIUM COMPLEXES CONTAINING FUNCTIONAL LIGANDS" Submitted by Wong Man Chung for the degree of Doctor of Philosophy at The University of Hong Kong ABSTRACT With the growing interest in the exploration of inorganic/ organometallic sensing materials, a series of mononuclear rhenium(I) and rhenium(V) and dinuclear rhenium(I) (DIC-18-C-6)Cl], complexes with crown ether pendants of formula [Re(CO) [{Re(CO) Cl}(DDIC)], [Re(CO)(DIC-S)Cl], [Re(CO)(DIC-3S)Cl], [Re(CO) (DIC- 3 2 3 3 3 Se)Cl], [Re(CO) (DPPZC)Cl] and [Re (PPh ) (C≡C-benzo-15-crown-5) ] have been 3 3 2 2 synthesized. The photophysical, electrochemical and cation-binding properties of these systems have been studied. The structure of [Re(CO) (DIC-Se)Cl] has been established by X-ray crystallography. The electronic absorption energies of the rhenium(I) complexes were found to be sensitive to the presence of metal cations. The stability constants of [Re(CO)(DIC-18-C-6)Cl] and [{Re(CO) Cl}(DDIC)] for alkali and 3 3 2 alkaline-earth metal cations have been determined by UV-visible spectrophotometry. The complexes [Re(CO)(DIC-S)Cl], [Re(CO)(DIC-3S)Cl] and [Re(CO) (DIC-Se)Cl] 3 3 3 showed a downfield shift of methylene protons adjacent to the sulphur or selenium atom on the crown ether moiety upon addition of silver ion in deuterated acetonitrile. Their stability constants for silver ion have also been determined by UV-visible and H NMR spectroscopies. Direct evidences for the formation of the inclusion species between the crown ether-containing rhenium(V) complex [Re (PPh ) (C≡C-benzo-15-crown-5) ] and 3 2 2 lithium or sodium ions were obtained from electrospray ionization-mass spectrometry. A series of mononuclear and dinuclear rhenium(I) complexes with thiolate and selenolate ligands, [Re(CO) (N-N)(S-C H -X-p)] and [{Re(CO) (N-N)} (μ-S-C H -X- 3 6 4 3 2 6 4] t p)], have been synthesized (N-N = bpy, Me -bpy, Bu -bpy, phen; X = CH, OCH, 2 2 3 3 C(CH ), Cl, F). Unsymmetrical dinuclear rhenium(I) thiolate complexes have been 3 3 prepared by utilizing the mononuclear complexes as precursors. Their electrochemical properties have also been studied. The photophysical behaviour of the dinuclear complexes has been studied. Attempts to investigate the photophysical behaviour of the mononuclear counterparts were unsuccessful owing to their low photo-stability. The crystal structures of the complexes [Re(CO) (phen)(SC H -OCH -p)], [Re(CO) ( Bu - 3 6 4 3 3 2 bpy)(SePh)], [{Re(CO) (bpy)} (μ-SC H -CH -p)]OTf, [Re(CO) (phen)(μ-SC H -OMe- 3 2 6 4 3 3 6 4 p)Re(CO) (bpy)]OTf and [Re(CO) (Me -bpy)(μ-SC H -Me-p)Re(CO) (NO -phen)]OTf 3 3 2 6 4 3 2 have also been determined. Besides, a series of luminescent rhenium(I) acetylide complexes with diimine ligands, [Re(CO) (N-N)(C≡C-R)] (N-N = bpy, Me -bpy, phen, NO -phen; R = Ph, C H - 3 2 2 6 4 Cl-p, C H -C H -p, C H -C≡CH-p, C H -N=N-C H -OC H, EEME), have been 6 4 8 17 6 4 6 4 6 4 12 25 synthesized and their photophysical and electrochemical properties studied. The X-ray crystal structure of [Re(CO) (bpy)(C≡C-Ph)] has been determined. An unsymmetrical dinuclear complex, [(bpy)(CO) Re-C≡C-C H -C≡C-C≡C-C H -C≡C-Re(CO) ( Bu -bpy)] 3 6 4 6 4 3 2 has been prepared by