Sulfur-containing heterocycles, where the S(R) moiety is located within the cyclic structure, have found tremendous applications in the fields of chemical, pharmaceutical, and materials sciences due to their unique chemical, biological and pharmaceutical activities. Recent years have witnessed increasing interest in sulfur-containing heterocycles, and new methods for their synthesis have been reported by adopting modern methodologies and technologies through insertion of sulfur dioxide. The main objective of this Account is to overview the latest major developments on the synthesis of sulfur-containing heterocyclic systems, mainly covering thermo-, photo- and electron-induced cyclization through the insertion of sulfur dioxide (SO₂). We aim to provide the readership with a comprehensive understanding of this topic and offer a positive outlook on the promising future of this field.

1 Introduction

2 Thermal-Induced Cyclization

3 Photoinduced Radical Cyclization

4 Electron-Induced Radical Cyclization

5 Conclusion