Thermal and Photochemical Reduction of Aqueous Chlorine by Ruthenium(II) Polypyridyl Complexes

Saha, Basudeb; Stanbury, David M.

doi:10.1021/ic9910920

Cited by 20 publications

(15 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The three [Ru(NN) 3 ] 2+ complexes {where NN = 2,2'-bipyridine (bpy), 4,4'-dimethyl-2,2'-bipyridine (dmbpy), 4,4'-di-t-butyl-2,2'-bipyridine (dtbpy)} were synthesized by reacting RuCl 3 ·3H 2 O with the corresponding ligands according to the procedure previously described [16,17]. The chloride salt of [Ru(bpy) 3 ] 2+ complex was treated with sodium tetrafluoroborate to get the BF 4ˉ salt [Ru(bpy) 3 ] (BF 4 ) 2.…”

Section: Methodsmentioning

confidence: 99%

Static Quenching of Ruthenium(II)-Polypyridyl Complexes by Gallic Acid and Quercetin in Aqueous and Micellar Media

Daniel¹,

Raj²

2014

ILCPA

View full text Add to dashboard Cite

The reactions of gallic acid and quercetin with the excited state Ru(II) complexes proceed through photoinduced electron transfer reaction in sodium dodecyl sulfate (SDS) and aqueous media at pH 11 and has been studied by luminescence quenching technique. The static nature of quenching is confirmed from the ground state absorption studies in both the media. The observed quenching rate constant (k q ) values are sensitive to the nature of the ligand, medium and the structure of the quenchers. The electrostatic interaction of the cationic complexes with the anionic micelle reduces the k q values in SDS compared to that in aqueous medium.

show abstract

Section: Methodsmentioning

confidence: 99%

Static Quenching of Ruthenium(II)-Polypyridyl Complexes by Gallic Acid and Quercetin in Aqueous and Micellar Media

Daniel¹,

Raj²

2014

ILCPA

View full text Add to dashboard Cite

show abstract

“…The three [Ru(NN) 3 ] 2+ complexes {where NN = 2,2′-bipyridine (bpy), 4,4′-dimethyl-2,2′-bipyridine (dmbpy), 4,4′-di-t-butyl-2,2′-bipyridine (dtbpy)} were synthesized by reacting RuCl 3 .3H 2 O with the corresponding ligands according to the procedure previously described [33,38,39] …”

Section: Methodsmentioning

confidence: 99%

Photoluminescence electron transfer quenching of ruthenium(II)-polypyridyl complexes with biologically important phenolate ions in aqueous acetonitrile solution

Daniel¹,

George²

2014

J IRAN CHEM SOC

View full text Add to dashboard Cite

involve the oxidation of phenols. Phenoxyl-type radicals are involved in biological redox processes and in the biosynthesis of natural products. The conversion of phenol to phenoxyl radical is of interest to chemists because of its involvement in important biological and industrial processes and in the degradation of chemical waste [8][9][10][11]. The one electron oxidation of phenolate to the resulting phenoxyl radical is a key step in the oxidation of phenols. The generation of phenoxyl radical involves either H-atom or electron abstraction from phenol and phenolate ion, respectively. The study of the kinetic and thermodynamic aspects of electron transfer (ET) to generate phenoxyl radicals bearing bulky groups in the ortho-and para-positions may help to understand the different biological roles of phenols [12][13][14][15].The oxidation potential of a polyphenol provides an estimate of the energy required to donate an electron; the lower the oxidation potential, lesser the energy required to donate an electron, hence it undergoes oxidation easily. The mechanism of oxidation of polyphenols and their stability in solution depend on pH [16,17]. The oxidation potential decreases with an increase in the number of phenolic -OH groups [18].Ruthenium polypyridyl complexes, such as [Ru(bpy) 3 ] 2+ (bpy = 2,2′-bipyridine), are among the most investigated in fields that include solar energy conversion [19,20], artificial photosynthesis [21], optical sensing [22,23], and luminescent probes for characterizing microheterogeneous environments, owing to their favorable photophysical properties, excited state reactivity, and chemical stability [24,25]. The excited state properties like emission lifetime, quantum yield, wavelength of emission maximum and redox potential of [Ru(bpy) 3 ] 2+ are largely affected by the introduction of electron-donating and electron-withdrawing groups in the 4,4′-position of 2,2′-bipyridine [26]. AbstractThe photoinduced electron transfer reactions of three Ru(II) complexes with phenolate ions of polyphenols (gallic acid, quercetin, p-coumaric acid, and ferulic acid) and thymol have been measured in 50 % aqueous acetonitrile at pH 11 and the observed quenching constant (k q ) values are sensitive to the nature of the ligand and the structure of the phenolate ion. The change of k q values with ΔG 0 is in accordance with the Marcus semiclassical theory of electron transfer. The static as well as dynamic nature of quenching is confirmed from the ground-state absorption studies. The reductive quenching of the Ru(II) complexes by the phenolate ions has been confirmed from the transient absorption spectra. The formation of phenoxyl radical as a transient is confirmed by its characteristic absorption at 400 nm.

show abstract

“…The structure of the quinones used in the present study was shown in fig 1. 2+ complexes with quinones were determined from Benesi-Hildebrand equation [16] using absorption intensity data [17].…”

Section: Int J Adv Res 5(2) 843-847mentioning

confidence: 99%

“…We present here a comprehensive study of interaction of ruthenium polypyridyl complexes with quinones in aqueous medium by using UV/Vis spectrophotometric parameters. , where NN = 2,2-bipyridine (bpy) and 4,4'-dimethyl-2,2 ' -bibyridine (dmbpy) were prepared by reacting RuCl 3 .3H 2 O with the corresponding ligands according to the known procedures [15,16]. The ligands and quinones used for this present work were procured from Sigma Aldrich.…”

Section: Introduction:-mentioning

confidence: 99%

Spectrophotometric Characterization of Ruthenium(ii) Polypyridyl Complexes With Para Quinones in Aqueous Medium.

Celin¹,

Raj.²

2017

IJAR

View full text Add to dashboard Cite

Two Ruthenium(II)) polypyridyl complexes [Ru(NN) 3 ] 2+ [(NN)→bpy , dmbpy] were synthesised. The binding interaction of these ruthenium complexes with para quinones have been studied by absorption spectral technique. These metal complexes have the absorption maximum in the range of 448 -458 nm. They have the emission maximum in the range 590-610 nm. The binding constant (k b ) for these complexes are determined from the Benesi-Hildebrand equation using the absorption intensity data. Structural effect plays an important role in the binding of the quinones with the complexes. …………………………………………………………………………………………………….... Introduction:-Quinones are ubiquitous in nature. p-quinones are important molecules in biological electron transport. They act as electron acceptor in photosynthesis [1][2][3]. They are well known for their citotoxicity. They have very high toxicological and pharmacological effects. They are used as anticancer drugs. They have antiviral, antifungal properties. Quinones have the capacity to accept electrons and are easy to protonate. They form stable hydrogen bonds. Due to their high mobility and small size, they have the property to get reduced. In order to understand the electron transfer properties of quinones, several photosensitizers have been designed. Inter and intra molecular electro transfer reactions have been studied.Their properties can be changed on complexation with proteins [4]. Transition metal complexes have received a considerable amount of attention over the past three decades [5][6][7]. Of these, particularly ruthenium (II) polypyridyl complexes have received much attention due to its tunable photophysical and photochemical properties. These complexes have a potential application in the field of photochemistry and biochemistry [8][9][10]. Recently reports show the advantages of ruthenium complexes in the field of cellular imaging and act as anticancer agents [11][12][13][14]. They act as good photocatalysts, particularly in the splitting of water molecule into O 2 and H 2 , used in dye sensitized solar cells and used in photodynamic therapy. We present here a comprehensive study of interaction of ruthenium polypyridyl complexes with quinones in aqueous medium by using UV/Vis spectrophotometric parameters. , where NN = 2,2-bipyridine (bpy) and 4,4'-dimethyl-2,2 ' -bibyridine (dmbpy) were prepared by reacting RuCl 3 .3H 2 O with the corresponding ligands according to the known procedures [15,16]. The ligands and quinones used for this present work were procured from Sigma Aldrich. Binding studies were carried out using double distilled water.All experiments were carried out at room temperature.

show abstract

Thermal and Photochemical Reduction of Aqueous Chlorine by Ruthenium(II) Polypyridyl Complexes

Cited by 20 publications

References 35 publications

Static Quenching of Ruthenium(II)-Polypyridyl Complexes by Gallic Acid and Quercetin in Aqueous and Micellar Media

Static Quenching of Ruthenium(II)-Polypyridyl Complexes by Gallic Acid and Quercetin in Aqueous and Micellar Media

Photoluminescence electron transfer quenching of ruthenium(II)-polypyridyl complexes with biologically important phenolate ions in aqueous acetonitrile solution

Spectrophotometric Characterization of Ruthenium(ii) Polypyridyl Complexes With Para Quinones in Aqueous Medium.

Contact Info

Product

Resources

About