Synlett 2017; 28(17): 2307-2310
DOI: 10.1055/s-0036-1590965
letter
© Georg Thieme Verlag Stuttgart · New York

Convenient and Clean Synthesis of Isatins by Metal-Free Oxidation of Oxindoles

Wen-Ting Wei*
School of Materials Science and Chemical Engineering, Ningbo University, Ningbo 315211, P. R. of China   eMail: weiwenting@nbu.edu.cn   eMail: lianghongze@nbu.edu.cn
,
Wei-Wei Ying
School of Materials Science and Chemical Engineering, Ningbo University, Ningbo 315211, P. R. of China   eMail: weiwenting@nbu.edu.cn   eMail: lianghongze@nbu.edu.cn
,
Wen-Ming Zhu
School of Materials Science and Chemical Engineering, Ningbo University, Ningbo 315211, P. R. of China   eMail: weiwenting@nbu.edu.cn   eMail: lianghongze@nbu.edu.cn
,
Yi Wu
School of Materials Science and Chemical Engineering, Ningbo University, Ningbo 315211, P. R. of China   eMail: weiwenting@nbu.edu.cn   eMail: lianghongze@nbu.edu.cn
,
Yi-Ling Huang
School of Materials Science and Chemical Engineering, Ningbo University, Ningbo 315211, P. R. of China   eMail: weiwenting@nbu.edu.cn   eMail: lianghongze@nbu.edu.cn
,
Yi-Qi Cao
School of Materials Science and Chemical Engineering, Ningbo University, Ningbo 315211, P. R. of China   eMail: weiwenting@nbu.edu.cn   eMail: lianghongze@nbu.edu.cn
,
Yi-Ning Wang
School of Materials Science and Chemical Engineering, Ningbo University, Ningbo 315211, P. R. of China   eMail: weiwenting@nbu.edu.cn   eMail: lianghongze@nbu.edu.cn
,
Hongze Liang*
School of Materials Science and Chemical Engineering, Ningbo University, Ningbo 315211, P. R. of China   eMail: weiwenting@nbu.edu.cn   eMail: lianghongze@nbu.edu.cn
› Institutsangaben
This research is sponsored by research funds of NBU (No. ZX2016000706), the foundation of Ningbo University (No. XYL17009), and the K. C. Wong Magna Fund in Ningbo University
Weitere Informationen

Publikationsverlauf

Received: 19. Mai 2017

Accepted after revision: 23. Juni 2017

Publikationsdatum:
21. Juli 2017 (online)


Abstract

A metal-free synthesis of isatins was achieved through the oxidative reactions of oxindoles with molecular oxygen in the presence of tert-butyl nitrite as an additive. This strategy provides a convenient and simple synthetic route to the construction of C=O bonds without the need for any catalyst or base. The attractive features of this reaction include its convenient procedure and mild reaction conditions.

Supporting Information

 
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