Palladium(II)-Catalyzed Alkyne Annulation Reactions for the Synthesis of Cyclopenta[b]naphthalene-1,4-diones

Abstract

A palladium-catalyzed C–H activation and alkyne annulation reaction of 2-hydroxy-3-(2-thienyl)naphthalene-1,4-diones has been developed for the construction of biologically important cyclopenta[b]naphthalene-1,4-dione derivatives. This reaction proceeds through hydroxy-group-directed heteroaryl C(sp²)–H activation, insertion of two molecules of an alkyne, and dehydrative cyclization pathways.

Key words

annulation - C–H bond activation - cyclopentanaphthalenediones - palladium catalysis - alkyne insertion

Publication History

Received: 27 February 2025

Accepted after revision: 02 May 2025

Accepted Manuscript online:
02 May 2025

Article published online:
13 June 2025

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