A simple and efficient synthesis of imidazoquinoxalines and spiroquinoxalinones via pictect-spengler reaction using Wang resin

Abstract

An efficient approach for the synthesis of various imidazoquinoxalines and spiroquinoxalinones has been reported from 2-(1H-imidazol-1-yl) aniline and different aldehydes using Wang-OSO₃H as a reusable catalyst to get in good yields. The reaction condition has been optimized by screening in various solvents and a gram scale experiment has also demonstrated. Further, the substrate scope of the reaction has also been well demonstrated.

Graphical Abstract

Keywords:

• Wang-OSO₃H
• imidazoquinoxaline
• spiroquinoxalinones
• recyclable catalyst

Additional information

Funding

The authors would like to thank Dr. Reddy’s Laboratory, Hyderabad for providing facilities to carry out this work. One of the authors Dr. Krishnaji acknowledges CHRIST (Deemed to be University), Bangalore for funding Major Research Project [MRP # MRPDSC-1723].