Pub Date : 2021-09-06DOI: 10.5772/intechopen.99730
Yuta Tsubonouchi, Eman A. Mohamed, Zaki N. Zahran, M. Yagi
Polypyridyl ruthenium(II) complexes have been widely researched as promising functional molecules. We have found unique photoisomerization reactions of polypyridyl ruthenium(II) aquo complexes. Recently we have attempted to provide insight into the mechanism of the photoisomerization of the complexes and distinguish between the distal−/proximal-isomers in their physicochemical properties and functions. Moreover, polypyridyl ruthenium(II) aquo complexes have been intensively studied as active water oxidation catalysts (WOCs) which are indispensable for artificial photosynthesis. The catalytic aspect and mechanism of water oxidation by the distal-/proximal-isomers of polypyridyl ruthenium(II) aquo complexes have been investigated to provide the guided thought to develop more efficient molecular catalysts for water oxidation. The recent progress on the photoisomerization and water oxidation of polypyridyl ruthenium(II) aquo complexes in our group are reviewed to understand the properties and functions of ruthenium complexes.
{"title":"Mechanisms of Photoisomerization and Water Oxidation Catalysis of Ruthenium(II) Aquo Complexes","authors":"Yuta Tsubonouchi, Eman A. Mohamed, Zaki N. Zahran, M. Yagi","doi":"10.5772/intechopen.99730","DOIUrl":"https://doi.org/10.5772/intechopen.99730","url":null,"abstract":"Polypyridyl ruthenium(II) complexes have been widely researched as promising functional molecules. We have found unique photoisomerization reactions of polypyridyl ruthenium(II) aquo complexes. Recently we have attempted to provide insight into the mechanism of the photoisomerization of the complexes and distinguish between the distal−/proximal-isomers in their physicochemical properties and functions. Moreover, polypyridyl ruthenium(II) aquo complexes have been intensively studied as active water oxidation catalysts (WOCs) which are indispensable for artificial photosynthesis. The catalytic aspect and mechanism of water oxidation by the distal-/proximal-isomers of polypyridyl ruthenium(II) aquo complexes have been investigated to provide the guided thought to develop more efficient molecular catalysts for water oxidation. The recent progress on the photoisomerization and water oxidation of polypyridyl ruthenium(II) aquo complexes in our group are reviewed to understand the properties and functions of ruthenium complexes.","PeriodicalId":21336,"journal":{"name":"Ruthenium - an Element Loved by Researchers [Working Title]","volume":"24 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82206554","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In electrochemiluminescence (ECL) studies, Tris (bipyridine)ruthenium(II) chloride (Ru(bpy)3 2+) and its derivatives have been used as primary luminophores since 1972. The flexible solubility in both aqueous and non-aqueous medium and the remarkable intrinsic properties like chemical, optical and desirable electrochemical behavior drives the researcher to use Ru(bpy)3 2+ and its derivatives as highly active ECL probes in modern analytical science. Novel surface modification of Ru(bpy)3 2+ based ECL platforms are highly useful in the selective and sensitive detection of biomolecules, DNA analysis, immunoassays detection, and imaging of the biologically important molecules in cells and tissue of living organisms. This chapter discusses and highlights the most significant works in Ru(bpy)3 2+ based ECL properties of reaction mechanisms and their applications.
{"title":"Ruthenium-Tris-Bipyridine Derivatives as a Divine Complex for Electrochemiluminescence Based Biosensor Applications","authors":"Chikkili Venkateswara Raju, Mathavan Sornambigai, Shanmugam Senthil Kumar","doi":"10.5772/INTECHOPEN.96819","DOIUrl":"https://doi.org/10.5772/INTECHOPEN.96819","url":null,"abstract":"In electrochemiluminescence (ECL) studies, Tris (bipyridine)ruthenium(II) chloride (Ru(bpy)3 2+) and its derivatives have been used as primary luminophores since 1972. The flexible solubility in both aqueous and non-aqueous medium and the remarkable intrinsic properties like chemical, optical and desirable electrochemical behavior drives the researcher to use Ru(bpy)3 2+ and its derivatives as highly active ECL probes in modern analytical science. Novel surface modification of Ru(bpy)3 2+ based ECL platforms are highly useful in the selective and sensitive detection of biomolecules, DNA analysis, immunoassays detection, and imaging of the biologically important molecules in cells and tissue of living organisms. This chapter discusses and highlights the most significant works in Ru(bpy)3 2+ based ECL properties of reaction mechanisms and their applications.","PeriodicalId":21336,"journal":{"name":"Ruthenium - an Element Loved by Researchers [Working Title]","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88316581","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-05-11DOI: 10.5772/INTECHOPEN.96466
R. Alsaiari
The role of ruthenium as a heterogeneous catalyst for epoxidation reaction has not been investigated extensively. Therefore, the purpose of this chapter is to provide overview of the epoxidation of alkene using ruthenium catalysts. The chapter is divided into two main sections. The first section is about epoxidation of alkene using supported ruthenium catalysts, while the second using ruthenium complexes (homogenous catalysts).
{"title":"Ruthenium Catalyst for Epoxidation Reaction","authors":"R. Alsaiari","doi":"10.5772/INTECHOPEN.96466","DOIUrl":"https://doi.org/10.5772/INTECHOPEN.96466","url":null,"abstract":"The role of ruthenium as a heterogeneous catalyst for epoxidation reaction has not been investigated extensively. Therefore, the purpose of this chapter is to provide overview of the epoxidation of alkene using ruthenium catalysts. The chapter is divided into two main sections. The first section is about epoxidation of alkene using supported ruthenium catalysts, while the second using ruthenium complexes (homogenous catalysts).","PeriodicalId":21336,"journal":{"name":"Ruthenium - an Element Loved by Researchers [Working Title]","volume":"57 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88609767","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-05-07DOI: 10.5772/INTECHOPEN.96464
N. Tyagi, Gongutri Borah, Pitambar Patel, D. Ramaiah
Over the past few decades, Ru catalyzed transfer hydrogenation (TH) and asymmetric transfer hydrogenation (ATH) reactions of unsaturated hydrocarbons, imine, nitro and carbonyl compounds have emerged as economic and powerful tools in organic synthesis. These reactions are most preferred processes having applications in the synthesis of fine chemicals to pharmaceuticals due to safe handling as these do not require hazardous pressurized H2 gas. The catalytic activity and selectivity of Ru complexes were investigated with a variety of ligands based on pincer NHC, cyclophane, half-sandwich, organophosphine etc. These ligands coordinate to Ru center in a proper orientation with a labile group replaced by H-source (like methanol, isopropanol, formic acid, dioxane, THF), which facilitate the β-hydrogen transfer to generate metal hydride species (Ru-H) and produce desired reduced product. This chapter describes the recent advances in TH and ATH reactions with homogeneous and heterogeneous Ru catalysts having different ligand environments and mechanistic details leading to their sustainable industrial applications.
{"title":"Recent Advances in Ru Catalyzed Transfer Hydrogenation and Its Future Perspectives","authors":"N. Tyagi, Gongutri Borah, Pitambar Patel, D. Ramaiah","doi":"10.5772/INTECHOPEN.96464","DOIUrl":"https://doi.org/10.5772/INTECHOPEN.96464","url":null,"abstract":"Over the past few decades, Ru catalyzed transfer hydrogenation (TH) and asymmetric transfer hydrogenation (ATH) reactions of unsaturated hydrocarbons, imine, nitro and carbonyl compounds have emerged as economic and powerful tools in organic synthesis. These reactions are most preferred processes having applications in the synthesis of fine chemicals to pharmaceuticals due to safe handling as these do not require hazardous pressurized H2 gas. The catalytic activity and selectivity of Ru complexes were investigated with a variety of ligands based on pincer NHC, cyclophane, half-sandwich, organophosphine etc. These ligands coordinate to Ru center in a proper orientation with a labile group replaced by H-source (like methanol, isopropanol, formic acid, dioxane, THF), which facilitate the β-hydrogen transfer to generate metal hydride species (Ru-H) and produce desired reduced product. This chapter describes the recent advances in TH and ATH reactions with homogeneous and heterogeneous Ru catalysts having different ligand environments and mechanistic details leading to their sustainable industrial applications.","PeriodicalId":21336,"journal":{"name":"Ruthenium - an Element Loved by Researchers [Working Title]","volume":"5 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82692586","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-04-16DOI: 10.5772/INTECHOPEN.97034
T. Müller
With the rising emphasis on efficient and highly selective chemical transformations, the field of ruthenium-catalysed hydrogenation and hydrogenolysis reactions has grown tremendously over recent years. The advances are triggered by the detailed understanding of the catalytic pathways that have enabled researchers to improve known transformations and realise new transformations in biomass conversion. Starting with the properties of ruthenium, this chapter introduces the concept of the catalytic function as a basis for rational design of ruthenium catalysts. Emphasis is placed on discussing the principles of dissociative adsorption of hydrogen. The principles are then applied to the conversion of typical biomolecules such as cellulose, hemicellulose and lignin. Characteristic features make ruthenium catalysis one of the most outstanding tools for implementing sustainable chemical transformations.
{"title":"Hydrogenation and Hydrogenolysis with Ruthenium Catalysts and Application to Biomass Conversion","authors":"T. Müller","doi":"10.5772/INTECHOPEN.97034","DOIUrl":"https://doi.org/10.5772/INTECHOPEN.97034","url":null,"abstract":"With the rising emphasis on efficient and highly selective chemical transformations, the field of ruthenium-catalysed hydrogenation and hydrogenolysis reactions has grown tremendously over recent years. The advances are triggered by the detailed understanding of the catalytic pathways that have enabled researchers to improve known transformations and realise new transformations in biomass conversion. Starting with the properties of ruthenium, this chapter introduces the concept of the catalytic function as a basis for rational design of ruthenium catalysts. Emphasis is placed on discussing the principles of dissociative adsorption of hydrogen. The principles are then applied to the conversion of typical biomolecules such as cellulose, hemicellulose and lignin. Characteristic features make ruthenium catalysis one of the most outstanding tools for implementing sustainable chemical transformations.","PeriodicalId":21336,"journal":{"name":"Ruthenium - an Element Loved by Researchers [Working Title]","volume":"39 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78690696","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-04-08DOI: 10.5772/INTECHOPEN.97071
Masa-aki Haga
Substitutionally inert ruthenium complexes bearing benzimidazole derivatives have unique electrochemical and photochemical properties. In particular, proton coupled electron transfer (PCET) in ruthenium–benzimidazole complexes leads to rich redox chemistry, which allows e.g. the tuning of redox potentials or switching by deprotonation. Using the background knowledge from acquired from their solution-state chemistry, Ru complexes immobilized on electrode surfaces have been developed and these offer new research directions toward functional molecular devices. The integration of surface-immobilized redox-active Ru complexes with multilayer assemblies via the layer-by-layer (LbL) metal coordination method on ITO electrodes provides new types of functionality. To control the molecular orientation of the complexes on the ITO surface, free-standing tetrapodal phosphonic acid anchor groups were incorporated into tridentate 2,6-bis(benzimidazole-2-yl)pyridine or benzene ligands. The use of the LbL layer growth method also enables “coordination programming” to fabricate multilayered films, as a variety of Ru complexes with different redox potentials and pKa values are available for incorporation into homo- and heterolayer films. Based on this strategy, many functional devices, such as scalable redox capacitors for energy storage, photo-responsive memory devices, proton rocking-chair-type redox capacitors, and protonic memristor devices have been successfully fabricated. Further applications of anchored Ru complexes in photoredox catalysis and dye-sensitized solar cells may be possible. Therefore, surface-confined Ru complexes exhibit great potential to contribute to the development of advanced functional molecular devices.
{"title":"Surface-Confined Ruthenium Complexes Bearing Benzimidazole Derivatives: Toward Functional Devices","authors":"Masa-aki Haga","doi":"10.5772/INTECHOPEN.97071","DOIUrl":"https://doi.org/10.5772/INTECHOPEN.97071","url":null,"abstract":"Substitutionally inert ruthenium complexes bearing benzimidazole derivatives have unique electrochemical and photochemical properties. In particular, proton coupled electron transfer (PCET) in ruthenium–benzimidazole complexes leads to rich redox chemistry, which allows e.g. the tuning of redox potentials or switching by deprotonation. Using the background knowledge from acquired from their solution-state chemistry, Ru complexes immobilized on electrode surfaces have been developed and these offer new research directions toward functional molecular devices. The integration of surface-immobilized redox-active Ru complexes with multilayer assemblies via the layer-by-layer (LbL) metal coordination method on ITO electrodes provides new types of functionality. To control the molecular orientation of the complexes on the ITO surface, free-standing tetrapodal phosphonic acid anchor groups were incorporated into tridentate 2,6-bis(benzimidazole-2-yl)pyridine or benzene ligands. The use of the LbL layer growth method also enables “coordination programming” to fabricate multilayered films, as a variety of Ru complexes with different redox potentials and pKa values are available for incorporation into homo- and heterolayer films. Based on this strategy, many functional devices, such as scalable redox capacitors for energy storage, photo-responsive memory devices, proton rocking-chair-type redox capacitors, and protonic memristor devices have been successfully fabricated. Further applications of anchored Ru complexes in photoredox catalysis and dye-sensitized solar cells may be possible. Therefore, surface-confined Ru complexes exhibit great potential to contribute to the development of advanced functional molecular devices.","PeriodicalId":21336,"journal":{"name":"Ruthenium - an Element Loved by Researchers [Working Title]","volume":"88 17 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84066701","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}