Sustainable Oxidation of Sulfides to Sulfoxides: Recent Advances in Catalyst Design and Oxygen‐Transfer Control (2021–2026)

Sustainable oxidation chemistry is not defined solely by the identity of the oxidant but by how oxygen transfer is controlled across the entire reaction system. In the case of sulfide oxidation, this challenge is particularly acute, as the selective formation of sulfoxides requires precise suppression of overoxidation pathways while maintaining functional‐group tolerance and practical applicability. This review surveys advances from 2021 to 2026 in transformation of sulfides to sulfoxides, focusing on how modern catalytic platforms address this balance between selectivity and sustainability. Rather than adopting a purely methodological classification, the discussion is organized around catalyst design and activation modes, including earth‐abundant metal catalysis, metal‐free and metal‐based photocatalysis, electrochemical systems, and organocatalytic oxygen‐transfer processes. Across these approaches, key parameters—oxidant, solvent, catalyst loading and preparation, substrate scope, recyclability, scalability, and selectivity—are evaluated comparatively to identify the features that define genuinely sustainable protocols. Particular attention is paid to the increasing role of heterogeneous and structured materials, such as polymeric photocatalysts, covalent organic frameworks, and hybrid systems, which enable improved control over oxygen activation and catalyst recovery. By highlighting both recent advances and persistent limitations, this review provides a critical framework for understanding sulfide oxidation as model reaction for sustainable oxidation chemistry.