Rhodium-Catalyzed Selective Nucleophilic Cyclization/Cross-Coupling of Two ortho-Alkynylanilines Bearing Differential N-Substituents

Org Lett. 2023 Aug 11;25(31):5890-5895. doi: 10.1021/acs.orglett.3c02180. Epub 2023 Aug 2.

Abstract

Herein, we reported an effective selective nucleophilic cyclization/cross-coupling cascade reaction of N-tosyl ortho-alkynylanilines and N-acyl ortho-alkynylanilines using Rh(COD)2BF4/tBuXantPhos as a catalyst. The present protocol features excellent chemo- and regioselectivity, high atom-economy, and a broad range of substrates. The mechanism studies indicated that the key to the success of this reaction is the powerful capacity of the rhodium catalyst to recognize the N-substituent group in the selective nucleophilic cyclization and selective alkyne insertion.