Palladium-catalyzed intramolecular diastereoselective dearomatization reaction of indoles with N-tosylhydrazones

Abstract

A novel highly diastereoselective palladium-catalyzed dearomative reaction of N-halobenzoyl o-haloaniline derivatives has been developed using functionalized N-tosylhydrazones as the coupling partners. This cascade dearomative protocol, which proceeds through a sequential...

Recent Advances in the Synthesis of Indolines via Dearomative Annulation of N‐acylindoles

“…Soon after, our group established a concise and straightforward palladium‐catalyzed intramolecular dearomatization reaction of N ‐halobenzoyl o ‐haloaniline derivatives using N ‐tosylhydrazones as the coupling partners, thereby to afford the synthetically valuable tetracyclic indoline skeletons with C2‐quaternary stereocenters (Scheme 33). [37] This tandem dearomative protocol, which tolerated a wide variety of functional groups, proceeded through a sequential dearomative carbopalladation, migratory insertion, and β ‐hydride elimination sequence and enabled access to a broad array of indoline derivatives in moderate to good yields and excellent diastereoselectivity. The products obtained in the reaction are valuable building frameworks which could participate in significant downstream synthetic transformations via the late‐stage of C−O double bond and C−C double bond.…”

Palladium-catalyzed intramolecular Heck dearomative gem-difluorovinylation of indoles

“…46–49 At present, the production of polycyclic indoline scaffolds has been established by palladium-catalyzed intramolecular Heck dearomatization of indoles (Scheme 1c). 50–68 On the one hand, 1,2-difunctionalization of indoles is achieved when the resulting benzyl-Pd species are captured with diverse nucleophiles that can effectively form various C–X (H, C, N, O, P, B, and Si) bonds. On the other hand, the reactions can be terminated by β-H elimination to construct CC double bonds.…”

“…On the other hand, the reactions can be terminated by β-H elimination to construct CC double bonds. 48,60,64–66 However, limited precursors restrict the installation of functionalized CC double bonds. Inspired by our first attempt at dearomatization of indoles, 67 we present herein an innovative idea for synthesizing gem -difluoroalkenes from N -(2-bromobenzoyl)indoles and ClCF 2 COONa.…”

Rh(III)-Catalyzed Successive C–H Activations of 2-Phenyl-3H-indoles and Cyclization Cascades to Construct Highly Fused Indole Heteropolycycles

“…Polycyclic indoles are important and privileged drug scaffolds, which exist widely in natural products and drug molecules, − such as arboloscine, aspidospermidine, vindoline, (−)-terengganensine B, larutienine B, hinckendtine A, etc. (Figure ).…”