Back to Search
Start Over
Visible light-promoted intermolecular cyclization/aromatization of chalcones and 2-mercaptobenzimidazoles via an EDA complex and a mechanism study.
- Source :
-
Organic & biomolecular chemistry [Org Biomol Chem] 2022 Jun 29; Vol. 20 (25), pp. 5139-5144. Date of Electronic Publication: 2022 Jun 29. - Publication Year :
- 2022
-
Abstract
- Visible-light-promoted cyclization and aromatization of chalcones with 2-mercaptobenzimidazoles have been successfully developed to obtain diverse imidazo[2,1- b ]thiazoles, and C-S and C-N bonds were constructed in one step. The reaction uses oxygen in the air as an oxidant, and the method does not need an external photocatalyst or a transition metal catalyst. The strategy features mild conditions, a simple system, readily accessible feedstocks, and a friendly environment. UV absorption spectroscopy and control experiments have shown that the reaction mechanism involves the formation of an electron-donor-acceptor (EDA) complex from thiolate anions and chalcones. In order to verify the mechanism, we studied the structure and HOMO/LUMO of the EDA complex by density functional theory (DFT) calculations. The results show that the π-π stacking between chalcones and 2-mercaptobenzimidazoles will cause a red shift of the UV absorption wavelength in the presence of Cs <subscript>2</subscript> CO <subscript>3</subscript> , and also provide a theoretical basis for the electron transfer of EDA complexes.
- Subjects :
- Benzimidazoles
Cyclization
Light
Oxidants
Chalcones chemistry
Subjects
Details
- Language :
- English
- ISSN :
- 1477-0539
- Volume :
- 20
- Issue :
- 25
- Database :
- MEDLINE
- Journal :
- Organic & biomolecular chemistry
- Publication Type :
- Academic Journal
- Accession number :
- 35707997
- Full Text :
- https://doi.org/10.1039/d2ob00847e