Chiral Phosphoric Acid-Catalyzed Asymmetric Synthesis of Axially Chiral Arylpyrazole
Shujun Tong1, Jiaqi Pu1, Yu Qi1
1School of Chemistry and Chemical Engineering/State Key Laboratory Incubation Base for Green Processing of Chemical Engineering, Shihezi University, Shihezi, Xinjiang 832003, China.
Abstract:
A chiral phosphoric acid-catalyzed efficient, operationally simple, general method for straightforward syntheses of axially chiral arylpyrazole employing N-alkyl of 3-aryl-5-aminopyrazoles reacting with azonaphthalenes was achieved. A wide variety of axially chiral heterobiaryl diamines in generally good yields with excellent enantioselectivities were obtained under mild conditions. In addition, a scaled-up experiment and postmodification of the chiral product further highlighted the synthetic utility.
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