Simple and Efficient Microwave Assisted N-Alkylation of Isatin

Abstract

We present herein the results of microwave promoted N-alkylations of isatin (1)with different alkyl, benzyl and functionalized alkyl halides. Reactions were carried outunder different conditions, always employing methodologies compatible with MW assistedchemistry. Generation of isatin anion employing diverse bases and solvents or using thepreformed isatin sodium salt was tested. The best results were achieved using K2CO3 orCs2CO3 and a few drops of N,N-dimethylformamide or N-methyl-2-pyrrolidinone. Thesereactions present noteworthy advantages over those carried out employing conventionalheating.

Keywords

• Isatin
• N-alkylation
• microwave irradiation
• conventional heating
• isatin sodium salt