Rh(III)-Catalyzed Oxidative C–2 Coupling of N-Pyridinylindoles with Benzo[b]thiophene 1,1-Dioxides via C–H Bond Activation

Abstract

An efficient Rh­(III)-catalyzed cross-dehydrogenative coupling of N-pyridinylindoles with benzo­[b]­thiophene 1,1-dioxides has been developed through directing-group-assisted C–H activation. This transformation constructs a new C–C bond from two inert C–H bonds in a one-pot reaction. The present reaction is compatible with various functional groups with respect to indoles and benzothiophene­[b] 1,1-dioxides. Furthermore, the emission properties of synthesized compounds have been explored.

Rhodium-Catalyzed Annulations and Heck Coupling/Aza-Michael Addition for the Synthesis of Benzothiadiazinoisoquinoline 6,6-Dioxides and Benzothiadiazinoisoindole 5,5-Dioxides, Respectively

“…Based on the previous metal-catalyzed directing group-assisted C–H bond activation − and exposure in C–H and N–H bond formation reactions, a suitable mechanism is proposed to account for the present reaction (Scheme ). From the control experiment, it is relevant that the oxidation of 1e into 1E occurs.…”

Synthesis of Unsymmetrical Biheteroarenes via Dehydrogenative and Decarboxylative Coupling: a Decade Update

“…Very recently (in 2021), Parthasarathy team [35] reported a rhodium‐catalyzed directing group assisted oxidative C−H/C−H cross‐dehydrogenative coupling of electron‐deficient benzo[ b ]thiophene 1,1‐dioxides with N ‐pyridinylfindoles to construct a series of fluorescence active biheteroaryl compounds. According to the prescribed one‐pot methodology, 1 equiv.…”

Palladium-Catalyzed C2-Selective Oxidative Olefination of Benzo[b]thiophene 1,1-Dioxides with Styrenes and Acrylates

“… 13 Very recently, Parthasarathy achieved N -pyridinyl-assisted oxidative cross-dehydrogenative coupling of N -pyridinylindoles with benzo[ b ]thiophene 1,1-dioxides ( Scheme 1 c). 14 Herein, we would like to report a novel palladium-catalyzed C2-selective oxidative olefination of benzo[ b ]thiophene 1,1-dioxides with alkenes ( Scheme 1 d).…”

“…In 2019, N -chelator-directed diastereoselective oxidative annulation of benzo­[ b ]­thiophene 1,1-dioxides with amino quinolinamides via double C–H activation was developed by Nicholls and co-workers (Scheme b) . Very recently, Parthasarathy achieved N -pyridinyl-assisted oxidative cross-dehydrogenative coupling of N -pyridinylindoles with benzo­[ b ]­thiophene 1,1-dioxides (Scheme c) . Herein, we would like to report a novel palladium-catalyzed C2-selective oxidative olefination of benzo­[ b ]­thiophene 1,1-dioxides with alkenes (Scheme d).…”