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Current Organic Chemistry

Author(s): Gurpreet Kaur, Arvind Singh, Kiran Bala, Mamta Devi, Anjana Kumari, Sapna Devi, Rekha Devi, Vivek Kumar Gupta and Bubun Banerjee*

DOI: 10.2174/1385272822666190924182538

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Naturally Occurring Organic Acid-catalyzed Facile Diastereoselective Synthesis of Biologically Active (E)-3-(arylimino)indolin-2-one Derivatives in Water at Room Temperature

Page: [1778 - 1788] Pages: 11

  • * (Excluding Mailing and Handling)

Abstract

A simple, straightforward and efficient method has been developed for the synthesis of (E)-3-(arylimino)indolin-2-one derivatives and (E)-2-((4-methoxyphenyl)imino)- acenaphthylen-1(2H)-one. The synthesis of these biologically-significant scaffolds was achieved from the reactions of various substituted anilines and isatins or acenaphthaquinone, respectively, using commercially available, environmentally benign and naturally occurring organic acids such as mandelic acid or itaconic acid as catalyst in aqueous medium at room temperature. Mild reaction conditions, energy efficiency, good to excellent yields, environmentally benign conditions, easy isolation of products, no need of column chromatographic separation and the reusability of reaction media are some of the significant features of the present protocol.

Keywords: Aqueous medium, isatin based schiff base, itaconic acid, mandelic acid, organic acids as catalyst, room temperature reaction, sustainable synthesis.

Graphical Abstract

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