Recent Developments in the Direct Methylation of Electron-­Deficient N-Heteroarenes

Abstract

The direct introduction of methyl groups into electron-deficient N-heteroarenes has recently emerged as an efficient and promising strategy to afford methylated N-heteroarenes, which are important motifs in a variety of pharmaceuticals and biologically active molecules. Herein, three general state-of-the-art approaches including radical-mediated, transition-metal-catalyzed, or transition-metal-free direct C–H methylations of electron-deficient N-heteroarenes are highlighted.

1 Introduction

2 Radical-Mediated Methylation of Electron-Deficient N-Heteroarenes

3 Transition-Metal-Catalyzed Methylation of Electron-Deficient N-Heteroarenes

4 Transition-Metal-Free Methylation of Electron-Deficient N-Heteroarenes

5 Conclusions

Key words

N-heteroarenes - methylation - radical reaction - catalysis - transition-metal-free

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