Modern Dearomative Enlargement of Heteroaromatic Rings

Abstract

Breaking aromaticity by inserting additional atoms within the skeleton of heteroaromatic rings has gained significant attention over the years. As part of the emerging concept of ‘skeletal editing’, this short review retraces the recent progress made on dearomative enlargement reactions of both five- and six-membered heterocycles.

1 Introduction

2 Dearomative Enlargement of Five-Membered Rings

2.1 Pyrroles, Furans, Thiophenes and Their Fused Analogues

2.2 Pyrazoles, Isoxazoles, Isothiazoles and Their Fused Analogues

3 Dearomative Enlargement of Six-Membered Rings

4 Conclusion and Perspectives