Concise Report
Divergent Assembly of Functionalized Pyrazolo[1,5-a]pyridine Derivatives via [3+2] Cyclization of N-Aminopyridinium Salts with Various Unsaturated Hydrocarbons
Xiang Liu,
Shaohong Ma,
Shi Yan,
Xiaotian Shi,
Shuting Li,
Yanlong Ma,
Hua Cao,
Xiang Liu
School of Chemistry and Chemical Engineering, Guangdong Pharmaceutical University, Zhongshan, Guangdong, 528458 China
Search for more papers by this authorShaohong Ma
School of Chemistry and Chemical Engineering, Guangdong Pharmaceutical University, Zhongshan, Guangdong, 528458 China
Search for more papers by this authorShi Yan
School of Chemistry and Chemical Engineering, Guangdong Pharmaceutical University, Zhongshan, Guangdong, 528458 China
Search for more papers by this authorXiaotian Shi
School of Chemistry and Chemical Engineering, Guangdong Pharmaceutical University, Zhongshan, Guangdong, 528458 China
Search for more papers by this authorShuting Li
School of Chemistry and Chemical Engineering, Guangdong Pharmaceutical University, Zhongshan, Guangdong, 528458 China
Search for more papers by this authorYanlong Ma
School of Chemistry and Chemical Engineering, Guangdong Pharmaceutical University, Zhongshan, Guangdong, 528458 China
Search for more papers by this authorCorresponding Author
Hua Cao
School of Chemistry and Chemical Engineering, Guangdong Pharmaceutical University, Zhongshan, Guangdong, 528458 China
E-mail: [email protected]Search for more papers by this authorXiang Liu,
Shaohong Ma,
Shi Yan,
Xiaotian Shi,
Shuting Li,
Yanlong Ma,
Hua Cao,
Xiang Liu
School of Chemistry and Chemical Engineering, Guangdong Pharmaceutical University, Zhongshan, Guangdong, 528458 China
Search for more papers by this authorShaohong Ma
School of Chemistry and Chemical Engineering, Guangdong Pharmaceutical University, Zhongshan, Guangdong, 528458 China
Search for more papers by this authorShi Yan
School of Chemistry and Chemical Engineering, Guangdong Pharmaceutical University, Zhongshan, Guangdong, 528458 China
Search for more papers by this authorXiaotian Shi
School of Chemistry and Chemical Engineering, Guangdong Pharmaceutical University, Zhongshan, Guangdong, 528458 China
Search for more papers by this authorShuting Li
School of Chemistry and Chemical Engineering, Guangdong Pharmaceutical University, Zhongshan, Guangdong, 528458 China
Search for more papers by this authorYanlong Ma
School of Chemistry and Chemical Engineering, Guangdong Pharmaceutical University, Zhongshan, Guangdong, 528458 China
Search for more papers by this authorCorresponding Author
Hua Cao
School of Chemistry and Chemical Engineering, Guangdong Pharmaceutical University, Zhongshan, Guangdong, 528458 China
E-mail: [email protected]Search for more papers by this authorComprehensive Summary
Two reaction modes for metal-free [3 + 2] cyclization of N-aminopyridinium derivatives with β-alkoxyvinyl trifluoromethylketones have been described through selective C—O or C—O/C—C bond cleavage. This strategy can also be extended to the [3 + 2] cyclization of N-aminopyridinium derivatives with enaminones and bromoalkynes. A broad range of N-aminopyridinium, N-aminoquinolinium, and N-aminoisoquinolinium salts are well tolerated, enabling the divergent synthesis of trifluoroacylated, non-substituted, acylated, and brominated pyrazolo[1,5-a]pyridine derivatives (62 examples).
Supporting Information
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Appendix S1: Supporting Information |
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