An iron(ii)-based metalloradical system for intramolecular amination of C(sp2)–H and C(sp3)–H bonds: synthetic applications and mechanistic studies. Issue 40 (30th September 2022)

• Record Type: Journal Article
• Authors: Das, Sandip Kumar; Das, Subrata; Ghosh, Supratim; Roy, Satyajit; Pareek, Monika; Roy, Brindaban; Sunoj, Raghavan B.; Chattopadhyay, Buddhadeb
• Is Part Of: Chemical science. Volume 13:Issue 40(2022)
• Page Start: 11817
• Page End: 11828
• Publication Date: 2022-09-30
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/d2sc03505g
• Languages: English
• ISSNs: 2041-6520

Abstract

Abstract : A catalytic system for intramolecular C(sp 2 )–H and C(sp 3 )–H amination of substituted tetrazolopyridines has been successfully developed. Abstract : A catalytic system for intramolecular C(sp 2 )–H and C(sp 3 )–H amination of substituted tetrazolopyridines has been successfully developed. The amination reactions are developed using an iron-porphyrin based catalytic system. It has been demonstrated that the same iron-porphyrin based catalytic system efficiently activates both the C(sp 2 )–H and C(sp 3 )–H bonds of the tetrazole as well as azide-featuring substrates with a high level of regioselectivity. The method exhibited an excellent functional group tolerance. The method affords three different classes of high-value N-heterocyclic scaffolds. A number of important late-stage C–H aminations have been performed to access important classes of molecules. Detailed studies (experimental and computational) showed that both the C(sp 2 )–H and C(sp 3 )–H amination reactions involve a metalloradical activation mechanism, which is different from the previously reported electro-cyclization mechanism. Collectively, this study reports the discovery of a new class of metalloradical activation modes using a base metal catalyst that should find wide application in the context of medicinal chemistry, drug discovery and industrial applications.