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Photoredox Cross-Dehydrogenative Coupling of N-Aryl Glycines Mediated by Mesoporous Graphitic Carbon Nitride: An Environmentally Friendly Approach to the Synthesis of Non-Proteinogenic α-Amino Acids (NPAAs) Decorated with Indoles

[Image: see text] Indole-decorated glycine derivatives are prepared through an environmentally benign cross-dehydrogenative coupling between N-aryl glycine analogues and indoles (yield of ≤81%). Merging heterogeneous organocatalysis and photocatalysis, C–H functionalization has been achieved by sele...

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Autores principales: Poletti, Lorenzo, Ragno, Daniele, Bortolini, Olga, Presini, Francesco, Pesciaioli, Fabio, Carli, Stefano, Caramori, Stefano, Molinari, Alessandra, Massi, Alessandro, Di Carmine, Graziano
Formato: Online Artículo Texto
Lenguaje:English
Publicado: American Chemical Society 2022
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9207928/
https://www.ncbi.nlm.nih.gov/pubmed/35621232
http://dx.doi.org/10.1021/acs.joc.2c00474
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author Poletti, Lorenzo
Ragno, Daniele
Bortolini, Olga
Presini, Francesco
Pesciaioli, Fabio
Carli, Stefano
Caramori, Stefano
Molinari, Alessandra
Massi, Alessandro
Di Carmine, Graziano
author_facet Poletti, Lorenzo
Ragno, Daniele
Bortolini, Olga
Presini, Francesco
Pesciaioli, Fabio
Carli, Stefano
Caramori, Stefano
Molinari, Alessandra
Massi, Alessandro
Di Carmine, Graziano
author_sort Poletti, Lorenzo
collection PubMed
description [Image: see text] Indole-decorated glycine derivatives are prepared through an environmentally benign cross-dehydrogenative coupling between N-aryl glycine analogues and indoles (yield of ≤81%). Merging heterogeneous organocatalysis and photocatalysis, C–H functionalization has been achieved by selective C-2 oxidation of N-aryl glycines to afford the electrophilic imine followed by Friedel–Crafts alkylation with indole. The sustainability of the process has been taken into account in the reaction design through the implementation of a metal-free recyclable heterogeneous photocatalyst and a green reaction medium. Scale-up of the benchmark reaction (gram scale, yield of 69%) and recycling experiments (over seven runs without a loss of efficiency) have been performed to prove the robustness of the protocol. Finally, mechanistic studies were conducted employing electron paramagnetic resonance spectroscopy to unveil the roles of the photocatalyst and oxygen in the formation of odd-electron species.
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spelling pubmed-92079282022-06-21 Photoredox Cross-Dehydrogenative Coupling of N-Aryl Glycines Mediated by Mesoporous Graphitic Carbon Nitride: An Environmentally Friendly Approach to the Synthesis of Non-Proteinogenic α-Amino Acids (NPAAs) Decorated with Indoles Poletti, Lorenzo Ragno, Daniele Bortolini, Olga Presini, Francesco Pesciaioli, Fabio Carli, Stefano Caramori, Stefano Molinari, Alessandra Massi, Alessandro Di Carmine, Graziano J Org Chem [Image: see text] Indole-decorated glycine derivatives are prepared through an environmentally benign cross-dehydrogenative coupling between N-aryl glycine analogues and indoles (yield of ≤81%). Merging heterogeneous organocatalysis and photocatalysis, C–H functionalization has been achieved by selective C-2 oxidation of N-aryl glycines to afford the electrophilic imine followed by Friedel–Crafts alkylation with indole. The sustainability of the process has been taken into account in the reaction design through the implementation of a metal-free recyclable heterogeneous photocatalyst and a green reaction medium. Scale-up of the benchmark reaction (gram scale, yield of 69%) and recycling experiments (over seven runs without a loss of efficiency) have been performed to prove the robustness of the protocol. Finally, mechanistic studies were conducted employing electron paramagnetic resonance spectroscopy to unveil the roles of the photocatalyst and oxygen in the formation of odd-electron species. American Chemical Society 2022-05-27 2022-06-17 /pmc/articles/PMC9207928/ /pubmed/35621232 http://dx.doi.org/10.1021/acs.joc.2c00474 Text en © 2022 The Authors. Published by American Chemical Society https://creativecommons.org/licenses/by/4.0/Permits the broadest form of re-use including for commercial purposes, provided that author attribution and integrity are maintained (https://creativecommons.org/licenses/by/4.0/).
spellingShingle Poletti, Lorenzo
Ragno, Daniele
Bortolini, Olga
Presini, Francesco
Pesciaioli, Fabio
Carli, Stefano
Caramori, Stefano
Molinari, Alessandra
Massi, Alessandro
Di Carmine, Graziano
Photoredox Cross-Dehydrogenative Coupling of N-Aryl Glycines Mediated by Mesoporous Graphitic Carbon Nitride: An Environmentally Friendly Approach to the Synthesis of Non-Proteinogenic α-Amino Acids (NPAAs) Decorated with Indoles
title Photoredox Cross-Dehydrogenative Coupling of N-Aryl Glycines Mediated by Mesoporous Graphitic Carbon Nitride: An Environmentally Friendly Approach to the Synthesis of Non-Proteinogenic α-Amino Acids (NPAAs) Decorated with Indoles
title_full Photoredox Cross-Dehydrogenative Coupling of N-Aryl Glycines Mediated by Mesoporous Graphitic Carbon Nitride: An Environmentally Friendly Approach to the Synthesis of Non-Proteinogenic α-Amino Acids (NPAAs) Decorated with Indoles
title_fullStr Photoredox Cross-Dehydrogenative Coupling of N-Aryl Glycines Mediated by Mesoporous Graphitic Carbon Nitride: An Environmentally Friendly Approach to the Synthesis of Non-Proteinogenic α-Amino Acids (NPAAs) Decorated with Indoles
title_full_unstemmed Photoredox Cross-Dehydrogenative Coupling of N-Aryl Glycines Mediated by Mesoporous Graphitic Carbon Nitride: An Environmentally Friendly Approach to the Synthesis of Non-Proteinogenic α-Amino Acids (NPAAs) Decorated with Indoles
title_short Photoredox Cross-Dehydrogenative Coupling of N-Aryl Glycines Mediated by Mesoporous Graphitic Carbon Nitride: An Environmentally Friendly Approach to the Synthesis of Non-Proteinogenic α-Amino Acids (NPAAs) Decorated with Indoles
title_sort photoredox cross-dehydrogenative coupling of n-aryl glycines mediated by mesoporous graphitic carbon nitride: an environmentally friendly approach to the synthesis of non-proteinogenic α-amino acids (npaas) decorated with indoles
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9207928/
https://www.ncbi.nlm.nih.gov/pubmed/35621232
http://dx.doi.org/10.1021/acs.joc.2c00474
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