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A team led by Chen Qingan, a researcher at the Dalian Institute of Chemical Physics, Chinese Academy of Sciences, has developed a bromide-catalyzed chlorine transfer reaction. This reaction can utilize halogenated organic pollutants (HOPs) as halogen sources, thereby enabling the reuse of different HOPs. This strategy provides a new method for synthesizing halogenated products with high added value, as well as a new approach for the reuse of HOPs. Recently, the relevant findings were published in Nature Chemistry. Due to the excessive use of halides, large amounts of HOPs are released into the environment, posing serious hazards to the environment and human health. The reuse of HOPs not only provides a way to eliminate such substances, but also enables the synthesis of high-value-added products and reduces greenhouse gas emissions associated with raw material production. Chen Qing’an’s team has developed an alkyl bromide-catalyzed chlorine transfer reaction; this reaction can be used not only to synthesize α-chloro compounds with high added value but also to achieve the chlorohydroxylation of olefins. In addition, they conducted a series of control experiments and kinetic studies, finding that the reaction enables the transfer of chlorine between different molecules through halogen exchange. Guided by the mechanism, the team achieved the bromination of homoarenes using the brominated organic pollutant hexabromocyclododecane (HBCD). To further verify the practicality of this reaction, the researchers applied the chlorine transfer reaction to the reuse of chlorinated organic pollutants. Studies have found that common chlorinated organic pollutants such as chlorinated paraffins, DDT, chloromethylated polystyrene, and polyvinyl chloride (PVC) can all serve as sources of chlorine for transfer chlorination reactions. The researchers directly used HBCD as a catalyst and PVC as a chlorine source to rapidly synthesize α-chloro compounds, and through simple transformations, achieved the synthesis of the non-steroidal anti-inflammatory drugs naproxen, ibuprofen, and celecoxib. The study also found that waste PVC plastic can likewise serve as a chlorine source for synthesizing chlorinated products. Although these discarded plastics contain large amounts of plasticizers, they have no significant effect on the chlorination reaction; therefore, this reaction holds great promise for the reuse of HOPs.