Synlett 2016; 27(03): 387-390
DOI: 10.1055/s-0035-1560962
letter
© Georg Thieme Verlag Stuttgart · New York

Catalyst-Free Friedel–Crafts Alkylation of Imidazo[1,2-α]pyridines

Ke Li
College of Chemistry and Molecular Engineering, Henan Key Laboratory of Chemical Biology and Organic Chemistry, Zhengzhou University, No. 100 of Science Road, Zhengzhou 450001, P. R. of China   Email: mpsong@zzu.edu.cn   Email: xqhao@zzu.edu.cn
,
Xinju Zhu
College of Chemistry and Molecular Engineering, Henan Key Laboratory of Chemical Biology and Organic Chemistry, Zhengzhou University, No. 100 of Science Road, Zhengzhou 450001, P. R. of China   Email: mpsong@zzu.edu.cn   Email: xqhao@zzu.edu.cn
,
Shuai Lu
College of Chemistry and Molecular Engineering, Henan Key Laboratory of Chemical Biology and Organic Chemistry, Zhengzhou University, No. 100 of Science Road, Zhengzhou 450001, P. R. of China   Email: mpsong@zzu.edu.cn   Email: xqhao@zzu.edu.cn
,
Xin-Yue Zhou
College of Chemistry and Molecular Engineering, Henan Key Laboratory of Chemical Biology and Organic Chemistry, Zhengzhou University, No. 100 of Science Road, Zhengzhou 450001, P. R. of China   Email: mpsong@zzu.edu.cn   Email: xqhao@zzu.edu.cn
,
Yan Xu
College of Chemistry and Molecular Engineering, Henan Key Laboratory of Chemical Biology and Organic Chemistry, Zhengzhou University, No. 100 of Science Road, Zhengzhou 450001, P. R. of China   Email: mpsong@zzu.edu.cn   Email: xqhao@zzu.edu.cn
,
Xin-Qi Hao*
College of Chemistry and Molecular Engineering, Henan Key Laboratory of Chemical Biology and Organic Chemistry, Zhengzhou University, No. 100 of Science Road, Zhengzhou 450001, P. R. of China   Email: mpsong@zzu.edu.cn   Email: xqhao@zzu.edu.cn
,
Mao-Ping Song*
College of Chemistry and Molecular Engineering, Henan Key Laboratory of Chemical Biology and Organic Chemistry, Zhengzhou University, No. 100 of Science Road, Zhengzhou 450001, P. R. of China   Email: mpsong@zzu.edu.cn   Email: xqhao@zzu.edu.cn
› Author Affiliations
Further Information

Publication History

Received: 23 August 2015

Accepted after revision: 16 October 2015

Publication Date:
20 November 2015 (online)


Abstract

A catalyst-free Friedel–Crafts alkylation of imidazo[1,2-α]pyridines with β-nitrostyrenes was developed. Electron-donating and electron-withdrawing functional groups at various aromatic positions were well tolerated under our optimized conditions. This method provides an efficient and environmentally benign route to synthesize imidazo[1,2-α]pyridine-nitroalkane derivatives in moderate to excellent yields.

Supporting Information

 
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