The Experts below are selected from a list of 74856 Experts worldwide ranked by ideXlab platform
Tomislav Rovis - One of the best experts on this subject based on the ideXlab platform.
-
amide directed photoredox catalysed c c Bond Formation at unactivated sp 3 c h Bonds
Nature, 2016Co-Authors: Tomislav RovisAbstract:The Formation of carbon–carbon Bonds is achieved via directed cleavage of traditionally non-reactive carbon–hydrogen Bonds and their subsequent coupling with readily available alkenes. In two separate reports, Robert Knowles and colleagues, and John Chu and Tomislav Rovis report the selective homolysis of selected amidyl N–H Bonds through a photocatalytic proton-coupled electron-transfer process. The resulting radical enables C–H abstraction and radical alkylation at the unactivated 5 position on the aliphatic chain of the N-alkyl amide. As this method does not rely on pre-activation of the amidyl N–H Bond or the use of haloamides, it offers a potentially simpler solution than previous approaches to radical amidyls. Additionally, the subsequent 1,5-hydrogen-atom transfer offers a route to selective C–C Bond Formation in the presence of alkyl amides. Carbon–carbon (C–C) Bond Formation is paramount in the synthesis of biologically relevant molecules, modern synthetic materials and commodity chemicals such as fuels and lubricants. Traditionally, the presence of a functional group is required at the site of C–C Bond Formation. Strategies that allow C–C Bond Formation at inert carbon–hydrogen (C–H) Bonds enable access to molecules that would otherwise be inaccessible and the development of more efficient syntheses of complex molecules1,2. Here we report a method for the Formation of C–C Bonds by directed cleavage of traditionally non-reactive C–H Bonds and their subsequent coupling with readily available alkenes. Our methodology allows for amide-directed selective C–C Bond Formation at unactivated sp3 C–H Bonds in molecules that contain many such Bonds that are seemingly indistinguishable. Selectivity arises through a relayed photoredox-catalysed oxidation of a nitrogen–hydrogen Bond. We anticipate that our findings will serve as a starting point for functionalization at inert C–H Bonds through a strategy involving hydrogen-atom transfer.
-
Amide-directed photoredox-catalysed C–C Bond Formation at unactivated sp 3 C–H Bonds
Nature, 2016Co-Authors: John C. K. Chu, Tomislav RovisAbstract:Carbon-carbon (C-C) Bond Formation is paramount in the synthesis of biologically relevant molecules, modern synthetic materials and commodity chemicals such as fuels and lubricants. Traditionally, the presence of a functional group is required at the site of C-C Bond Formation. Strategies that allow C-C Bond Formation at inert carbon-hydrogen (C-H) Bonds enable access to molecules that would otherwise be inaccessible and the development of more efficient syntheses of complex molecules. Here we report a method for the Formation of C-C Bonds by directed cleavage of traditionally non-reactive C-H Bonds and their subsequent coupling with readily available alkenes. Our methodology allows for amide-directed selective C-C Bond Formation at unactivated sp3 C-H Bonds in molecules that contain many such Bonds that are seemingly indistinguishable. Selectivity arises through a relayed photoredox-catalysed oxidation of a nitrogen-hydrogen Bond. We anticipate that our findings will serve as a starting point for functionalization at inert C-H Bonds through a strategy involving hydrogen-atom transfer.
Gedu Satyanarayana - One of the best experts on this subject based on the ideXlab platform.
-
Superacid-Promoted Dual C–C Bond Formation by Friedel–Crafts Alkylation/Acylation of Cinnamate Esters: Synthesis of Indanones
Synthesis, 2015Co-Authors: Gedu Satyanarayana, Bokka Ramulu, Pedireddi NiharikaAbstract:Superacid-Promoted Dual C–C Bond Formation by Friedel–Crafts Alkylation/Acylation of Cinnamate Esters: Synthesis of Indanones
-
superacid promoted dual c c Bond Formation by friedel crafts alkylation acylation of cinnamate esters synthesis of indanones
Synthesis, 2015Co-Authors: Bokka Ramulu, Pedireddi Niharika, Gedu SatyanarayanaAbstract:Dual C–C Bond Formation was accomplished in one pot for the synthesis of a wide variety of indanones mediated by triflic acid. The reaction proceeds via an initial Michael-addition-type Friedel–Crafts alkylation followed by intramolecular acylation (cyclization). Significantly, the method was also successfully employed on more reactive β-diarylcinnamates using slightly different conditions.
-
Superacid-Promoted Dual C-C Bond Formation by Friedel-Crafts Alkylation and Acylation of Ethyl Cinnamates: Synthesis of Indanones
Synlett, 2013Co-Authors: Gedu Satyanarayana, Bokka Venkat Ramulu, Alavala Gopi Krishna ReddyAbstract:A superacid (triflic acid) promoted dual C-C Bond Formation via intermolecular Friedel-Crafts alkylation (Michael addition type) and intramolecular acylation for the efficient synthesis of 3-substituted indan-1-ones is presented. This method was successful in activating ethyl cinnamates towards dual aromatic electrophilic substitution. Moreover, it enabled us to synthesize novel spirotetracyclic system
Zhangjie Shi - One of the best experts on this subject based on the ideXlab platform.
-
transition metal catalyzed c c Bond Formation through the fixation of carbon dioxide
Chemical Society Reviews, 2011Co-Authors: Ku Huang, Zhangjie ShiAbstract:Carbon dioxide is an important carbon source in the atmosphere and is “problematic” toward the activities of human beings. Although carbon dioxide is a cheap, abundant and relatively nontoxic C1 source, its chemical transFormations have not been widely developed so far and are still far from synthetic applications, especially in the construction of the C–C Bond. This critical review summarizes the recent advances on transition-metal-catalyzed C–C Bond Formation through the fixation of carbon dioxide and their synthetic applications (124 references).
-
Transition-metal-catalyzed C–C Bond Formation through the fixation of carbon dioxide
Chemical Society reviews, 2011Co-Authors: Kun Huang, Chang‐liang Sun, Zhangjie ShiAbstract:Carbon dioxide is an important carbon source in the atmosphere and is “problematic” toward the activities of human beings. Although carbon dioxide is a cheap, abundant and relatively nontoxic C1 source, its chemical transFormations have not been widely developed so far and are still far from synthetic applications, especially in the construction of the C–C Bond. This critical review summarizes the recent advances on transition-metal-catalyzed C–C Bond Formation through the fixation of carbon dioxide and their synthetic applications (124 references).
Pedireddi Niharika - One of the best experts on this subject based on the ideXlab platform.
-
Superacid-Promoted Dual C–C Bond Formation by Friedel–Crafts Alkylation/Acylation of Cinnamate Esters: Synthesis of Indanones
Synthesis, 2015Co-Authors: Gedu Satyanarayana, Bokka Ramulu, Pedireddi NiharikaAbstract:Superacid-Promoted Dual C–C Bond Formation by Friedel–Crafts Alkylation/Acylation of Cinnamate Esters: Synthesis of Indanones
-
superacid promoted dual c c Bond Formation by friedel crafts alkylation acylation of cinnamate esters synthesis of indanones
Synthesis, 2015Co-Authors: Bokka Ramulu, Pedireddi Niharika, Gedu SatyanarayanaAbstract:Dual C–C Bond Formation was accomplished in one pot for the synthesis of a wide variety of indanones mediated by triflic acid. The reaction proceeds via an initial Michael-addition-type Friedel–Crafts alkylation followed by intramolecular acylation (cyclization). Significantly, the method was also successfully employed on more reactive β-diarylcinnamates using slightly different conditions.
Hui Chen - One of the best experts on this subject based on the ideXlab platform.
-
Remote C–C Bond Formation via visible light photoredox-catalyzed intramolecular hydrogen atom transfer
Organic & biomolecular chemistry, 2020Co-Authors: Hui ChenAbstract:Carbon–carbon Bonds comprise the major framework of organic molecules, rendering their Formation one of the most fundamental transFormations in synthetic organic chemistry. Visible light photoredox catalysis has recently been established as a powerful technique to construct molecular architectures that would otherwise be inaccessible under mild conditions. Photoredox catalysis combined with intramolecular hydrogen atom transfer (HAT) can serve as a unique tool for achieving remote C–C Bond Formation. In this review, the recent advances in remote C–C Bond Formation via photoredox-catalyzed intramolecular HAT are summarized.
-
Cu-Catalyzed Arylcarbocyclization of Alkynes with Diaryliodonium Salts through C–C Bond Formation on Inert C(sp3)–H Bond
Organic letters, 2014Co-Authors: Jing Peng, Chao Chen, Junjie Chen, Hui ChenAbstract:Copper-catalyzed arylcarbocyclization reaction of alkynes was realized with diaryliodonium salts through C–C Bond Formation on an inert C(sp3)–H Bond. This method provides an efficient cyclization of alkyl alkynes to generate carbocycles with good step-economy. Theoretical study revealed an interesting Cu-catalyzed concerted pathway of the C–C Bond Formation.
