Palladium-catalyzed oxidative C–H activation/annulation ofN-alkylanilines with bromoalkynes: access to functionalized 3-bromoindoles

Abstract

A straight-forward approach to the synthesis of 3-bromoindoles via palladium-catalyzed oxidative C–H activation/annulation of N-alkylanilines with bromoalkynes has been described. This protocol features in high atom economy, excellent chemo- and...

Metal‐Catalysed Synthesis of Benzofused Five‐Membered N/O/S‐Heterocycles, a Progressive Area in Synthetic Organic Chemistry

“…[27] In the same vein, Wu and co-workers devised a facile method for the oxidative CÀ H activation/annulation of N-alkylanilines with bromoalkynes in order to produce 3-bromoindoles. [28] In 2023, the same group published a successful approach for the construction of 2-phenylindoles 16 via palladium-catalysed annulation of anilines 14 with bromoalkynes 15 (Scheme 5). [29] Excellent regio-and stereo-selectivity as well as good functional group tolerance were observed in the reaction.…”

“…Over a time, C−H functionalization with transition metals became another alluring method for the synthesis of indoles [27] . In the same vein, Wu and co‐workers devised a facile method for the oxidative C−H activation/annulation of N‐alkylanilines with bromoalkynes in order to produce 3‐bromoindoles [28] . In 2023, the same group published a successful approach for the construction of 2‐phenylindoles 16 via palladium‐catalysed annulation of anilines 14 with bromoalkynes 15 (Scheme 5).…”

Palladium‐Catalyzed Tandem Cyclization of Bromoalkynes, Anilines and CO: Access to 1,3‐Substituted Maleimides

“…[2] Therefore, a series of efficient synthetic strategies to various heterocyclic compounds involving haloalkynes have been reported, including nucleophilic addition, [3] alkynylation [4] and annulation reactions. [5] Among them, our group recently has developed a palladiumcatalyzed nucleophilic addition/annulation of bromoalkynes with benzoic acids for the synthesis of isocoumarins. [6] Recently, we have reported the synthesis of 2-phenylindoles from bromoalkynes and anilines via nucleophilic addition/CÀ H functionalization strategy [7] (Scheme 1a).…”

Palladium-catalyzed ligand-regulated divergent synthesis of pyrrole[2,3-b]indoles and ureas from 2-ethynylanilines and isocyanides

“…11 We envisage that the key to success is applied to an elegant ligand for palladium-catalyzed reactions to adjust the reaction mode of isocyanide insertion. Based on our continuing interests in nucleopalladation 12 and isocyanide chemistry, 13 herein, we disclose a ligand-controlled palladium-catalyzed reaction of 2-ethynylaniline and isocyanides to achieve bicyclization products and oxidative amidation products with high selectivity.…”