| Autor: |
Ghosh P; Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai-400076, India., Maiti S; Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai-400076, India., Malandain A; Université Paris Saclay, CEA, Service de Chimie Bio-organique et Marquage, DMTS, F-91191 Gif-sur-Yvette, France., Raja D; Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai-400076, India., Loreau O; Université Paris Saclay, CEA, Service de Chimie Bio-organique et Marquage, DMTS, F-91191 Gif-sur-Yvette, France., Maity B; KAUST Catalysis Center (KCC), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia., Roy TK; Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai-400076, India., Audisio D; Université Paris Saclay, CEA, Service de Chimie Bio-organique et Marquage, DMTS, F-91191 Gif-sur-Yvette, France., Maiti D; Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai-400076, India.; Interdisciplinary Program in Climate Studies, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India.; National Center of Excellence CCU, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India. |
| Abstrakt: |
The direct utilization of carbon dioxide as an ideal one-carbon source in value-added chemical synthesis has garnered significant attention from the standpoint of global sustainability. In this regard, the photo/electrochemical reduction of CO 2 into useful fuels and chemical feedstocks could offer a great promise for the transition to a carbon-neutral economy. However, challenges in product selectivity continue to limit the practical application of these systems. A robust and general method for the conversion of CO 2 to the polarity-reversed carbon dioxide radical anion, a C1 synthon, is critical for the successful valorization of CO 2 to selective carboxylation reactions. We demonstrate herein a hydride and hydrogen atom transfer synergy driven general catalytic platform involving CO 2 •- for highly selective anti-Markovnikov hydrocarboxylation of alkenes via triple photoredox, hydride, and hydrogen atom transfer catalysis. Mechanistic studies suggest that the synergistic operation of the triple catalytic cycle ensures a low-steady-state concentration of CO 2 •- in the reaction medium. This method using a renewable light energy source is mild, robust, selective, and capable of accommodating a wide range of activated and unactivated alkenes. The highly selective nature of the transformation has been revealed through the synthesis of hydrocarboxylic acids from the substrates bearing a hydrogen atom available for intramolecular 1, n -HAT process as well as diastereoselective synthesis. This technology represents a general strategy for the merger of in situ formate generation with a synergistic photoredox and HAA catalytic cycle to provide CO 2 •- for selective chemical transformations. |
