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Synlett 2013; 24(1): 79-84
DOI: 10.1055/s-0032-1317923
letter
© Georg Thieme Verlag Stuttgart · New York

Synthesis of 3,4-Disubsituted Isoxazoles via Enamine [3+2] Cycloaddition

Qian-fa Jia
a   Allan H. Conney Laboratory for Anticancer Research, Guang Dong University of Technology, Guang Dong, 510006, P. R. of China
,
Pooi Ming Shurn Benjamin
b   Department of Chemistry, National University of Singapore, Block S15, Level 5, 3 Science Drive 3, 117543, Singapore   Fax: +65(677)91691   Email: chmwangj@nus.edu.sg
,
Jiayao Huang
b   Department of Chemistry, National University of Singapore, Block S15, Level 5, 3 Science Drive 3, 117543, Singapore   Fax: +65(677)91691   Email: chmwangj@nus.edu.sg
,
Zhiyun Du*
a   Allan H. Conney Laboratory for Anticancer Research, Guang Dong University of Technology, Guang Dong, 510006, P. R. of China
,
Xi Zheng
a   Allan H. Conney Laboratory for Anticancer Research, Guang Dong University of Technology, Guang Dong, 510006, P. R. of China
,
Kun Zhang
a   Allan H. Conney Laboratory for Anticancer Research, Guang Dong University of Technology, Guang Dong, 510006, P. R. of China
,
Allan H. Conney
a   Allan H. Conney Laboratory for Anticancer Research, Guang Dong University of Technology, Guang Dong, 510006, P. R. of China
,
Jian Wang*
a   Allan H. Conney Laboratory for Anticancer Research, Guang Dong University of Technology, Guang Dong, 510006, P. R. of China
b   Department of Chemistry, National University of Singapore, Block S15, Level 5, 3 Science Drive 3, 117543, Singapore   Fax: +65(677)91691   Email: chmwangj@nus.edu.sg
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Further Information

Publication History

Received: 05 November 2012

Accepted after revision: 23 November 2012

Publication Date:
10 December 2012 (online)

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Abstract

Enamine-triggered [3+2]-cycloaddition reactions of ­aldehydes and N-hydroximidoyl chlorides in the presence of tri­ethylamine give rise to 3,4-disubstituted isoxazoles upon oxidation of the cycloadduct 3,4,5-trisubstituted 5-(pyrrolidinyl)-4,5-dihydroisoxazoles. This offers a high yielding, regiospecific and metal-free synthetic route for the synthesis of 3,4-disubstituted isoxazoles.

Key words

isoxazole - enamines - 1,3-dipoles - [3+2] cycloaddition
 

  • References and Notes

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