Photocatalytic Formamide Synthesis via Coupling of Electrophilic and Nucleophilic Radicals over Atomically Dispersed Bi Sites.
Angew Chem Int Ed Engl
; : e202408379, 2024 Jul 06.
Article
em En
| MEDLINE
| ID: mdl-38970405
ABSTRACT
Formamide (HCONH2) plays a pivotal role in the manufacture of a diverse array of chemicals, fertilizers, and pharmaceuticals. Photocatalysis holds great promise for green fabrication of carbon-nitrogen (C-N) compounds owing to its environmental friendliness and mild redox capability. However, the selective formation of the C-N bond presents a significant challenge in the photocatalytic synthesis of C-N compounds. This work developed a photocatalytic radical coupling method for the formamide synthesis from co-oxidation of ammonia (NH3) and methanol (CH3OH). An exceptional formamide yield rate of 5.47 ± 0.03 mmol·gcat-1·h-1 (911.87 ± 0.05 mmol·gBi-1·h-1) was achieved over atomically dispersed Bi sites (BiSAs) on TiO2. An accumulation of 45.0 mmol·gcat-1 (0.2 g·gcat-1) of formamide was achieved after long-term illumination, representing the highest level of photocatalytic C-N compounds synthesis. The critical C-N coupling for formamide formation originated from the "σ-σ" interaction between electrophilic âCH2OH with nucleophilic âNH2 radical. The BiSAs sites facilitated the electron transfer between reactants and photocatalysts and enhanced the nucleophilic attack of âNH2 radical at the âCH2OH radical, thereby advancing the selective C-N bond formation. This work deepens the understanding of the C-N coupling mechanism and offers an alternative and intriguing photocatalytic approach for the efficient and sustainable production of C-N compounds.
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1
Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Revista:
Angew Chem Int Ed Engl
Ano de publicação:
2024
Tipo de documento:
Article
País de afiliação:
China