Recent Advances in Sulfine Chemistry: Synthesis, Properties, andSynthetic Applications (2015–2025)

Sulfines, a class of sulfur (IV)-containing heterocumulenes with the general structure X(Y)C=S=O, have attracted considerable interest due to their unique structural features and versatile reactivity in organic synthesis. This review provides a comprehensive overview of recent developments in sulfine chemistry from 2015 to the end of 2025. Significant progress has been made in synthetic methodologies, including the oxidation of thiocarbonyl compounds, base-induced eliminations, hetero-Wolff rearrangements of α-diazo sulfoxides, and other innovative approaches. These methods have enabled access to a wide range of sulfines with varying steric and electronic properties. In medicinal and natural product chemistry, sulfine intermediates have been identified in key biosynthetic pathways and bioactive molecule synthesis. Structural studies have elucidated intriguing aspects such as nonlinear geometry and stereoisomerism through advanced spectroscopic and computational analyses. Furthermore, sulfines have been served as valuable synthons in diverse transformations, including nucleophilic reactions and cycloadditions, leading to the construction of complex molecular architectures such as quinoxaline-2-thiols, quinoxalines, thiazoles, dithiohydantoins, and macrocyclic compounds. In conclusion, this survey underscores the growing importance of sulfines as powerful intermediates in organic synthesis and suggests future directions for research, including the development of catalytic asymmetric processes and the exploration of new applications in materials and pharmaceutical sciences.