A nonsymmetrical PNN pincer ligand[6-(^(t)Bu_(2)PNH)C_(5)H_(4)N-2-(3-Mes)C_(3)H_(2)N_(2)]and its corresponding cobalt-N_(2)complex were synthesized and characterized.By the stoichiometric reaction of the PNN ligand li...A nonsymmetrical PNN pincer ligand[6-(^(t)Bu_(2)PNH)C_(5)H_(4)N-2-(3-Mes)C_(3)H_(2)N_(2)]and its corresponding cobalt-N_(2)complex were synthesized and characterized.By the stoichiometric reaction of the PNN ligand lithium salt with CoCl_(2),the complex 3,(PNN)CoCl,was obtained.Then,reduction of 3 with NaBHEt3under a dinitrogen atmosphere yielded complex 5,(PNN)Co(Ⅰ)(η^(1)-N_(2)).Single-crystal X-ray analysis,IR spectrum,and DFT calculations revealed that the dinitrogen in 5 was only weakly reduced by the cobalt center.The reactions of 5 with carbon monoxide and 2,6-dimethylphenyl isocyanide gave carbonyl and isocyanide complexes 6 and 7 with the release of N_(2),respectively.Furthermore,these cobalt complexes,especially complex 5,demonstrated the capacity to convert dinitrogen to N(TMS)_(3)with moderate efficiency.展开更多
The conversion of N_(2)to NH_(3)holds great importance due to the essential role of NH_(3)in fertilizer production,energy storage and the synthesis of key industrial chemicals.Development of novel methods for N_(2)tra...The conversion of N_(2)to NH_(3)holds great importance due to the essential role of NH_(3)in fertilizer production,energy storage and the synthesis of key industrial chemicals.Development of novel methods for N_(2)transformation is a worthwhile goal and researchers have turned their attention to electrochemical N_(2)reduction as a potentially sustainable solution.The development of molecular electrocatalysts has gained considerable momentum over the last decades,and this review focuses on the advances and challenges in the field of molecular electrochemical nitrogen fixation and aims to inspire further research into the realm of nitrogen fixation chemistry from an electrochemical perspective.展开更多
Comprehensive Summary,The Haber-Bosch process,which is used for ammonia(NH3)synthesis,requires vast amounts of energy,accounting for approximately 1%—2%of the world's annual energy consumption.Therefore,researche...Comprehensive Summary,The Haber-Bosch process,which is used for ammonia(NH3)synthesis,requires vast amounts of energy,accounting for approximately 1%—2%of the world's annual energy consumption.Therefore,researchers in both industry and academia are interested in developing sustainable and environmentally friendly methods for synthesizing nitrogenous compounds at ambient conditions using renewable energy sources such as visible light.While several examples of thermal activation of dinitrogen molecules have been demonstrated using various transition metals and ligand frameworks,the use of light to weaken or split the strong N—N bond has been less explored.This article presents an overview of molecular complexes capable of dinitrogen photocleavage and provides mechanistic insights into the photoactivation process through experimental and theoretical studies.We believe this review will provide readers with an in-depth understanding of the current state-of-the-art and future research perspectives,particularly in the use of visible light for dinitrogen activation and transformation.展开更多
基金supported by the National Natural Science Foundation of China(Nos.21988101 and 22201013)Beijing Natural Science Foundation(No.2222008)supported by the High-performance Computing Platform of Peking University。
文摘A nonsymmetrical PNN pincer ligand[6-(^(t)Bu_(2)PNH)C_(5)H_(4)N-2-(3-Mes)C_(3)H_(2)N_(2)]and its corresponding cobalt-N_(2)complex were synthesized and characterized.By the stoichiometric reaction of the PNN ligand lithium salt with CoCl_(2),the complex 3,(PNN)CoCl,was obtained.Then,reduction of 3 with NaBHEt3under a dinitrogen atmosphere yielded complex 5,(PNN)Co(Ⅰ)(η^(1)-N_(2)).Single-crystal X-ray analysis,IR spectrum,and DFT calculations revealed that the dinitrogen in 5 was only weakly reduced by the cobalt center.The reactions of 5 with carbon monoxide and 2,6-dimethylphenyl isocyanide gave carbonyl and isocyanide complexes 6 and 7 with the release of N_(2),respectively.Furthermore,these cobalt complexes,especially complex 5,demonstrated the capacity to convert dinitrogen to N(TMS)_(3)with moderate efficiency.
基金supported by the National Natural Science Foundation of China(21988101)。
文摘The conversion of N_(2)to NH_(3)holds great importance due to the essential role of NH_(3)in fertilizer production,energy storage and the synthesis of key industrial chemicals.Development of novel methods for N_(2)transformation is a worthwhile goal and researchers have turned their attention to electrochemical N_(2)reduction as a potentially sustainable solution.The development of molecular electrocatalysts has gained considerable momentum over the last decades,and this review focuses on the advances and challenges in the field of molecular electrochemical nitrogen fixation and aims to inspire further research into the realm of nitrogen fixation chemistry from an electrochemical perspective.
基金the National Natural Science Foundation of China(Nos.21988101 and 22201013)Beijing Natural Science Foundation(No.2222008).
文摘Comprehensive Summary,The Haber-Bosch process,which is used for ammonia(NH3)synthesis,requires vast amounts of energy,accounting for approximately 1%—2%of the world's annual energy consumption.Therefore,researchers in both industry and academia are interested in developing sustainable and environmentally friendly methods for synthesizing nitrogenous compounds at ambient conditions using renewable energy sources such as visible light.While several examples of thermal activation of dinitrogen molecules have been demonstrated using various transition metals and ligand frameworks,the use of light to weaken or split the strong N—N bond has been less explored.This article presents an overview of molecular complexes capable of dinitrogen photocleavage and provides mechanistic insights into the photoactivation process through experimental and theoretical studies.We believe this review will provide readers with an in-depth understanding of the current state-of-the-art and future research perspectives,particularly in the use of visible light for dinitrogen activation and transformation.