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Current Organic Synthesis

Author(s): Yuan Jiang, Yanling Tang, Hui Gao*, Gaoxiong Rao and Zewei Mao*

DOI: 10.2174/1570179419666220225115017

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Copper(II)-catalyzed Synthesis of Benzoxazoles from Inactive 2-chloroanilides

Page: [819 - 823] Pages: 5

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Abstract

Aim and Objective: Benzoxazoles are of great importance in natural products, pharmaceutical agents as well as synthetic intermediates. Although many works on the construction of benzoxazoles by Cu-catalyzed intramolecular O-arylation of ortho-haloanilides have been reported, only a few reports about transition metal-catalyzed synthesis of benzoxazoles from inactive 2-chloroanilides so far. This work aimed to explore a green and cheap protocol for intramolecular O-arylation of inactive 2-chloroanilides to prepare 2-arylbenzoxazoles.

Materials and Methods: We found that Cu(acac)2/1,10-Phen complex was beneficial to intramolecular O-arylation of 2-chloroanilides using K2CO3 as a base in EtOH at 90 °C to prepare benzoxazoles.

Results: An efficient and green method was developed for Cu(II)-catalyzed intramolecular Oarylation of inactive 2-chloroanilides.

Conclusion: In this way, many 2-arylbenzoxazoles were prepared in good yields.

Keywords: Cu-catalyzed, O-arylation, benzoxazoles, 2-chloroanilides, heterocyclic compounds, pharmaceutical agents.

Graphical Abstract

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