Dehydrogenative [2 + 2 + 1] Heteroannulation Using a Methyl Group as a One-Carbon Unit: Access to Pyrazolo[3,4-c]quinolines

 

Dehydrogenative [2 + 2 + 1] Heteroannulation Using a Methyl Group as a One-Carbon Unit: Access to Pyrazolo[3,4-c]quinolines

Guo-Bo Deng^†, Hai-Bing Li^†, Xu-Heng Yang^†, Ren-Jie Song^*†, Ming Hu^†, and Jin-Heng Li^*†‡

^† State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, China

^‡ State Key Laboratory of Applied Organic Chemistry Lanzhou University, Lanzhou 730000, China

Org. Lett., Article ASAP

DOI: 10.1021/acs.orglett.6b00618

Publication Date (Web): April 28, 2016

Copyright © 2016 American Chemical Society

*E-mail: srj0731@hnu.edu.cn., *E-mail: jhli@hnu.edu.cn.

http://pubs.acs.org/doi/abs/10.1021/acs.orglett.6b00618

 A practical and straightforward access to pyrazolo[3,4-c]quinolines by molecular sieve mediated dehydrogenative [2 + 2 + 1] heteroannulation of N-(o-alkenylaryl)imines with aryldiazonium salts is described using a sp³-hybrid carbon atom as a one-carbon unit. The reaction enables the formation of three new chemical bonds, a C–C bond and two C–N bonds, in a single reaction and features simple operation and excellent functional group tolerance.

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