Facile synthesis of 3-(pyrazol-1-yl) succinimides from Ag₂CO₃ -catalyzed aza-Michael addition of pyrazoles to maleimides

Abstract

Herein, an effective and facile synthesis of 3-(pyrazol-1-yl) succinimides is first presented through silver-catalyzed aza-Michael addition of pyrazoles to maleimides. In the presence of 5 mol% of Ag₂CO₃, various pyrazoles smoothly reacted with maleimides in dichloroethane at 100 °C, to generate 3-(pyrazol-1-yl) succinimides in excellent yields. Notably, 3-substituted asymmetric pyrazoles exclusively give 3-pyrazolyl succinimides in excellent yields possibly due to the steric bulk of the 3-substituent excluding the formation of addition products of N². The method can also extend to gram scale.

Graphical Abstract

Keywords:

• Maleimide
• Michael addition
• pyrazole
• silver carbonate
• succinimide

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

We are grateful to Funds for the Natural Science Foundation of Jilin Province, China[YDZJ202201ZYTS364, 20210101128JC]; the Foundation of Science and Technology Research Projects of Jilin Provincial Department of Education (JJKH20210001KJ); Program for Innovative Research Team of Baicheng Normal University[012010].