A theoretical investigation of the reaction mechanisms for C-H and C-C bond activation processes in the reaction of Ni with cycloalkanes C,,H2. (n = 3-7) is carried out. For the Ni + CnH2, (n = 3, 4) reactions, t...A theoretical investigation of the reaction mechanisms for C-H and C-C bond activation processes in the reaction of Ni with cycloalkanes C,,H2. (n = 3-7) is carried out. For the Ni + CnH2, (n = 3, 4) reactions, the major and minor reaction channels involve C-C and C-H bond activations, respectively, whereas Ni atom prefers the attacking of C-H bond over the C-C bond in CnH2n (n = 5=7). The results are in good agreement with the experimental study. In all cases, intermediates and transition states along the reaction paths of interest are characterized, It is found that both the C-H and C-C bond activation processes are proposed to proceed in a one-step manner via one transition state. The overall C-H and C-C bond activation processes are exothermic and involve low energy barriers, thus transition metal atom Ni is a good mediator for the activity of cycloalkanes CnH2n (n = 3 -7).展开更多
Single-atom catalysis,the catalysis by single-atom catalysts(SACs),has attracted considerable attention in recent years as a new frontier in the heterogeneous catalysis field.SACs have the advantages of both homogeneo...Single-atom catalysis,the catalysis by single-atom catalysts(SACs),has attracted considerable attention in recent years as a new frontier in the heterogeneous catalysis field.SACs have the advantages of both homogeneous catalysts(isolated active sites)and heterogeneous catalysts(stable and easy to separate),and are thus predicted to be able to bridge the homo-and heterogeneous catalysis.This prediction was first experimentally demonstrated in 2016.In this mini-review,we summarize the few homogeneous catalysis progresses reported recently where SACs have exhibited promising application:a)Rh/ZnO and Rh/CoO SAC have been used successfully in hydroformylation of olefin of which the activity are comparable to the homogeneous Wilkinson’s catalyst;b)a Pt/Al2O3 SAC has shown excellent performance in hydrosilylation reaction;and c)M-N-C SACs(M=Fe,Co etc.)have been applied in the activation of C–H bonds.All of these examples suggest that fabrication of suitable SACs could provide a new avenue for the heterogenization of homogeneous catalysts.These pioneering works shed new light on the recognition of single-atom catalysis in bridging the homo-and heterogeneous catalysis.展开更多
Heterogenization of organic-macrocyclic metal catalysts is one of the simplest and most efficient methods for effective separation of products and cyclic application of a catalyst.By using an environmentally friendly ...Heterogenization of organic-macrocyclic metal catalysts is one of the simplest and most efficient methods for effective separation of products and cyclic application of a catalyst.By using an environmentally friendly Mn-corrolazine catalyst as the building unit,which can directly oxidize organic substrates under oxygen atmosphere and mild conditions,we theoretically constructed a novel two-dimensional(2D)Mn-corrolazine nanocatalytic material with high catalytic activity.In this material,each Mn atom maintains its electronic configuration in the monomer and can directly activate O2 as the single-atom catalyst(SAC)center to form a radical-like[Mn]-O-O under mild visible-light irradiation conditions.The newly generated[Mn]–O–O can efficiently and selectively oxidize C–H bonds to form alcohol species through H-abstraction and the rebound reaction.Moreover,the catalytic reaction is easily regulated by an external electric field along its intrinsic Mn–O–O reaction axis.The current study provides a theoretical foundation for further experimental studies and practical applications of the Mn-corrolazine-based SAC.展开更多
基金Supported by the National Natural Science Foundation of China(No.20773014 and 20933001)the Research Foundation of Education Bureau of Hebei Province(No.Z2011115)+3 种基金the 111 Project of China(No.B07012)the Natural Science Foundation of Hebei Province(No.B2012105002)the Research Foundation of Tangshan Administration of Science&Technology(121302011a)the Research Foundation of Tangshan normal college(2013A04)for their support of this work
文摘A theoretical investigation of the reaction mechanisms for C-H and C-C bond activation processes in the reaction of Ni with cycloalkanes C,,H2. (n = 3-7) is carried out. For the Ni + CnH2, (n = 3, 4) reactions, the major and minor reaction channels involve C-C and C-H bond activations, respectively, whereas Ni atom prefers the attacking of C-H bond over the C-C bond in CnH2n (n = 5=7). The results are in good agreement with the experimental study. In all cases, intermediates and transition states along the reaction paths of interest are characterized, It is found that both the C-H and C-C bond activation processes are proposed to proceed in a one-step manner via one transition state. The overall C-H and C-C bond activation processes are exothermic and involve low energy barriers, thus transition metal atom Ni is a good mediator for the activity of cycloalkanes CnH2n (n = 3 -7).
基金supported by National Natural Science Foundation of China(21606222,21776270)Postdoctoral Science Foundation(2017M621170,2016M601350)~~
文摘Single-atom catalysis,the catalysis by single-atom catalysts(SACs),has attracted considerable attention in recent years as a new frontier in the heterogeneous catalysis field.SACs have the advantages of both homogeneous catalysts(isolated active sites)and heterogeneous catalysts(stable and easy to separate),and are thus predicted to be able to bridge the homo-and heterogeneous catalysis.This prediction was first experimentally demonstrated in 2016.In this mini-review,we summarize the few homogeneous catalysis progresses reported recently where SACs have exhibited promising application:a)Rh/ZnO and Rh/CoO SAC have been used successfully in hydroformylation of olefin of which the activity are comparable to the homogeneous Wilkinson’s catalyst;b)a Pt/Al2O3 SAC has shown excellent performance in hydrosilylation reaction;and c)M-N-C SACs(M=Fe,Co etc.)have been applied in the activation of C–H bonds.All of these examples suggest that fabrication of suitable SACs could provide a new avenue for the heterogenization of homogeneous catalysts.These pioneering works shed new light on the recognition of single-atom catalysis in bridging the homo-and heterogeneous catalysis.
文摘Heterogenization of organic-macrocyclic metal catalysts is one of the simplest and most efficient methods for effective separation of products and cyclic application of a catalyst.By using an environmentally friendly Mn-corrolazine catalyst as the building unit,which can directly oxidize organic substrates under oxygen atmosphere and mild conditions,we theoretically constructed a novel two-dimensional(2D)Mn-corrolazine nanocatalytic material with high catalytic activity.In this material,each Mn atom maintains its electronic configuration in the monomer and can directly activate O2 as the single-atom catalyst(SAC)center to form a radical-like[Mn]-O-O under mild visible-light irradiation conditions.The newly generated[Mn]–O–O can efficiently and selectively oxidize C–H bonds to form alcohol species through H-abstraction and the rebound reaction.Moreover,the catalytic reaction is easily regulated by an external electric field along its intrinsic Mn–O–O reaction axis.The current study provides a theoretical foundation for further experimental studies and practical applications of the Mn-corrolazine-based SAC.