DABCO-catalyzed synthesis of 3-substituted-3-hydroxyindolin-2-ones in aqueous media

ABSTRACT

An efficient and greener protocol for easy access to 3-susbstituted-3-hydroxy-2-oxindoles by the reaction with various substituted isatins and acetophenones is described. This protocol is widely applicable for a variety of isatins and acetophenones using water as a reaction media and 1,4-diazabicyclo[2.2.2]octane (DABCO) as catalyst with shorter reaction time and good to excellent yield of products.

GRAPHICAL ABSTRACT

KEYWORDS:

• Acetophenone
• aldol reaction
• DABCO
• hydroxyindolin-2-one
• isatin

Acknowledgments

K. N. T. thanks the Director, CSIR-CDRI, Lucknow (mentor institute of NIPER, Raebareli), and P. K. Shukla, Project Director, NIPER, Raebareli for their support and encouragement in carrying out this research work. SAIF-CSIR-CDRI, Lucknow, is greatly acknowledged for providing spectral data. This is NIPER-RBL Communication No. 02. The authors declare no conflict of interest.