Synthesis And Properties Of Novel Ru(Ⅱ) Polypyridine Complexes

Ru(â…¡) polypyridyl complexes have attracted explosive interest in recent yearsdue to their versatile ground and excited-state photophysical, photochemical andredox properties. It is playing a key role in the development of photochemistry,photophysics, photocatalysis, NLO material, electrochemistry, electron and energytransfer, and molecular recognition. The paper is focused on the design and synthesisof Ru(â…¡) polypyridyl complexes and the investigation of their electron and energytransfer, proton-induce emission switch, and molecular recognition properties.This paper consists of six chapters1. It was given a brief review of the design and synthesis, photophysical andelectrochemical properties of Ru(â…¡) polypyridyl complexes and its applications on thefields of electron and energy transfer, pH emission switch, cation recognition, ationrecognition and DNA recognition.2. Polynuclear Ru(â…¡) polypyridyl complexes have received special attention inrecent years in connection with the design of molecular electron devices forphotoinduced electron and energy transfer. Properties of such complexes are criticallydependent on the size, shape, and electronic nature of the bridging ligand. Herein, wesynthesized six polypodal ligands L^1-6 and corresponding Ru(â…¡) polypyridinecomplexes based on 4,5-diazafluoren, investigated the influence of the differentligangs to the properties of complexes.Six ligands were involved in this chapter:2,2',2"-Tris((4,5-diazafluoren-9-yliminoxy)ethyl)amine (L¹)1,3,5-Tris((4,5-diazafluoren-9-yliminoxy)methyl))-2,4,6-trimethylbenzene (L²)2,2',2"-Tris[(4,5-diazafluoren-9-ylimino)phenoxyethyl]amine (L³)1,3,5-Tris[(4,5-diazafluoren-9-ylimino)phenoxymethyl]-2,4,6-trimethylbenzene (L⁴)1,1',1 "-Tris[(4,5-diazafluoren-9-ylimino)phenoxymethyl]-1"'-(p-tosyloxymethyl)-methane(L⁵)1,2,3,4,5,6-hexakis[(4,5-diazafluoren-9-yliminoxy)methyl)]benzene(L⁶)3. Heteronuclear Ru(â…¡) polypyridyl complexes have drawn increasing attention in recent years in connection with the design of molecular electron devices forphotoinduced electron and energy transfer. The design of the bridging ligand is one ofthe key steps in realizing molecular electronic devices based on polynuclearcomplexes. We synthesized two polypyridyl ligands L^7-8 by cross-coupling reactionsof ethynylferrocene with 5-bromo-2,2'-bipyridine, and 3-bromo-1,10-phenanthrolinerespectively. Corresponding Ru(â…¡) complex was prepared and the electron and energytransfer between the Ru(â…¡) and Fe(â…¡) center was investigated.Two ligands were involved in this chapter:5-(2-ferrocenylethynyl)-2,2'-bipyridine (L⁷)3-(2-ferrocenylethynyl)-1,10-phenanthroline (L⁸)4. Ru(â…¡) polypyridyl complexes have been proved to be particularly useful in pHsensor applications, because their outstanding photophysical and electrochemicalproperties are quite sensitive to environmental pH variation. We synthesized onepolypyridyl ligand L⁹ and corresponding trinuclear Ru(â…¡) polypyridyl complexcontaining imidazole fragment. The UV-vis and fluorescence properties of thiscomplex in response to pH changes were investigated.One ligand was involved in this chapter:1,3,5-tris(1,10-phenanthroline-[5,6-d]imidazol-2-yl)benzene (L⁹)5. Much attention has been devoted to the design and synthesis of ligands withan ion recognition unit attached to Ru(â…¡) polypyridyl core. Interactions between therecognition center and the substrate can be converted into physical signs, such asemission and UV-vis, so they have great potential utility in fields as diverse asmedical analysis, environmental monitoring and so on. Li, Na and K play vital rolesin living cells. Benzocrown etner can recognise alkali or alkaline-earth metal ions.Herein, we synthesized eight ligands L^10-17 with macrocyclic unit benzo-15-crown-5,benzo-12-crown-4, dibenzo-14-crown-4, dibenzo-18-crown-6 and their Ru(â…¡)complexes, investagated photophysical properties of these complexes in response toalkali or alkaline-earth metal ions binding.Eight ligands were involved in this chapter: 4'-(imidazo[4,5-f] [1,10]phenanthrolin-2-yl)benzo- 12-crown-4 (L¹⁰)4'-(imidazo [4,5-f] [1,10]phenanthrolin-2-yl)benzo- 15-crown-5 (L¹¹)cis-di(4,5-diazafluoren-9-ylimino)dibenzo-14-crown-4 (L¹²)trans-di(4,5-diazafluoren-9-ylimino)dibenzo-14-crown-4 (L¹³)1,4,8,11-tetraoxaeyelotetradeeyl[2,3:9,10]bis-dipyrido[3,2-a:2'3'-e]phenazine (L¹⁴)cis-di(4,5-diazafluoren-9-ylimino)dibenzo-18-crown-6 (L¹⁵)trans-di(4,5-diazafluoren-9-ylimino)dibenzo-18-crown-6 (L¹⁶)1,4,7,10,13,16-hexaoxaeyeloetadeeyl[2,3:11,12]bis-dipyrido[3,2-a:2'3'-e]phenazine(L¹⁷)6. Particular interest has been focused on the measurement of Mg²⁺ and Ca²⁺ inbiological system, because Mg²⁺ and Ca²⁺ are the most abundant divalent cation inliving cells, and plays vital roles in many cellular processes. We synthesized nineligands L^18-26 with open-chain crown ether, and corresponding Ru(â…¡) complexesRu-L^18-26. These complexes have rich photophysieal and electrochemical properties.Alkali or alkaline-earth metal ions binding have influence on the properties of thesecomplexes. Alkali and alkaline-earth metal ions have no obvious modifying effect onthe photophysical and electrochemical properties of Ru-L^18,21,24. Ru-L^19,22,25 show thehighest binding ability toward Mg²⁺, Ru-L^20,23,26 exhibit selective recognition abilityto Ca²⁺ among five cations examined.1,7-bis-(4-(4,5 -diazafluoren-9-ylhydrazinyl)benzylidene)-1,4,7-trioxaheptane (L¹⁸)1,10-bis-(4-(4,5-diazafluoren-9-ylhydrazinyl)benzylidene)-1,4,7,10-tetraoxadecane(L¹⁹)1,13-his-(4-(4,5-diazafluoren-9-ylhydrazinyl)benzylidene)- 1,4,7,10, 13-pentaoxatridecane (L²⁰)1,7-bis-(4-(4,5-diazafluoren-9-ylimino)phenyl)-1,4,7-trioxaheptane (L²¹)1,10-bis-(4-(4,5-diazafluoren-9-ylimino)phenyl)-1,4,7,10-tetraoxadecane (L²²)1,13-bis-(4-(4,5-diazafluoren-9-ylimino)phenyl)-1,4,7,10, 13-pentaoxalridecane (L²³)1,7-bis-(4,5-diazafluoren-9-ylimino)-1,4,7-trioxaheptane (L²⁴)1,10-bis-(4,5-diazafluoren-9-ylimino)-1,4,7,10-tetraoxadecane (L²⁵)1,13-bis-(4,5-diazafluoren-9-ylimino)-1,4, 7,10, 13-pentaoxatridecane (L²⁶)...