Rh(iii)-Catalyzed [5 + 1] Annulation of 2-alkenylanilides and 2-alkenylphenols with Allenyl Acetates

Overview

Journal Chem Sci

Publisher Royal Society of Chemistry

Specialty Chemistry

Date 2022 Mar 21

PMID 35308860

Authors

Anurag Singh

Rahul K Shukla

Chandra M R Volla

Affiliations

Soon will be listed here.

Abstract

Herein, we report a mild and highly regioselective Rh(iii)-catalyzed non-oxidative [5 + 1] vinylic C-H annulation of 2-alkenylanilides with allenyl acetates, which has been elusive so far. The reaction proceeds vinylic C-H activation, regioselective 2,3-migratory insertion, β-oxy elimination followed by nucleophilic cyclization to get direct access to 1,2-dihydroquinoline derivatives. The strategy was also successfully extended to C-H activation of 2-alkenylphenols for constructing chromene derivatives. In the overall [5 + 1] annulation, the allene serves as a one carbon unit. The acetate group on the allene is found to be crucial both for controlling the regio- and chemoselectivity of the reaction and also for facilitating β-oxy elimination. The methodology was scalable and also further extended towards late stage functionalization of various natural products.

Citing Articles

Pd(ii)-catalyzed β- and γ-C-(sp)-H dienylation with allenyl acetates.

Shukla R, Nair A, Volla C Chem Sci. 2023; 14(4):955-962.

PMID: 36755729 PMC: 9890605. DOI: 10.1039/d2sc05188e.

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