Abstract
A new and a simple approach toward synthesis of 1,3,5-trisubstituted pyrazoles from chalcone arylhydrazones via oxidative cyclization has been achieved. 2,3-Dichloro-5,6-dicyano-1,4-benzoquinone was successfully used as an oxidizing agent to give excellent yields of pyrazoles.
GRAPHICAL ABSTRACT
![](/cms/asset/5d58e88e-5a6f-4840-a9f4-05616d2ebc66/lsyc_a_531492_o_uf0001.gif)
ACKNOWLEDGMENT
The authors thank the Department of Science and Technology, government of Goa, for financial assistance.
Notes
a Conditions: N-Arylhydrazones, DDQ (2 equivalents), dichloromethane, rt, stir, 2 h.
b Yields after recrystallization.
c Determined mp compared to lit. mp.[3f,4b,8–15,17–19]
a Conditions: N-Arylhydrazones, DDQ (2 equivalents), dichloromethane, rt, stir, 2 h.
b Yields after recrystallization.
c Determined mp compared to lit. mp.[4b,15,16]