Related Experiment Video
Updated: Feb 6, 2026

Preparation of Contiguous Bisaziridines for Regioselective Ring-Opening Reactions
Published on: July 28, 2022
Regioselective C2-Sulfonylation of Indoles and Pyrroles via SO2 Insertions
Rekha Bai1, Wan-Lin Cheng1, Chun-Yu Peng1
1Department of Chemistry, National Chung Hsing University, Taichung City 40227, Taiwan (R.O.C.).
Abstract:
A molecular iodine-catalyzed three-component cascade reaction of indoles/pyrroles, anilines, and DABSO has been developed, providing C2-sulfonylated indoles/pyrroles in good to excellent yields. The transformation proceeds via the in situ generation of the arylsulfonyl radical from the reaction of anilines, tBuONO, and DABSO, followed by controlled formation of a carbon-centered radical intermediate. In this radical-mediated cascade reaction, DABSO acts as the sulfone (SO2) source while tBuONO facilitates the generation of reactive species. Moreover, this one-pot transformation proceeds under mild conditions, exhibits a broad substrate scope, and offers an efficient and sustainable strategy for the construction of C2-sulfonated indoles and pyrroles.
Related Concept Videos
Regioselectivity of Electrophilic Additions-Peroxide Effect
Regioselectivity and Stereochemistry of Hydroboration
Hydroboration proceeds in a concerted fashion with the attack of borane on the π bond, giving a cyclic four-centered transition state. The –BH2 group is bonded to the less substituted carbon and –H to the more substituted carbon. The concerted nature requires the simultaneous addition of –H and –BH2 across the same face of the alkene giving syn stereochemistry.
Regioselective Formation of Enolates
Regioselectivity and Stereochemistry of Acid-Catalyzed Hydration
Regioselectivity of Electrophilic Additions to Alkenes: Markovnikov's Rule
The hydrohalogenation of an unsymmetrical alkene can yield two haloalkane products, depending on which vinylic carbon takes up the halogen. However, one product usually predominates, where hydrogen adds to the vinylic carbon bearing the...
Porin Insertion in the Outer Mitochondrial Membrane
Three models describe the assembly of porins by the SAM complex and their insertion into the outer membrane. Model 1 suggests that porins are assembled outside the SAM channel as the...

