A metal-freesynthesis of oxindoles was achieved through the (NH4)2S2O8-mediated halocarbocyclization of alkenes. This protocol provides a practical and environmentally benign method for the construction of halo-containing oxindoles in water. The advantages of this reaction are its good functional group tolerance and mild reaction conditions. On the basis of experimental observations, a plausible reaction
通过(NH 4)2 S 2 O 8介导的烯烃的卤代碳环化反应实现了羟吲哚的无金属合成。该协议为在水中构建含卤素的羟吲哚提供了一种实用且对环境无害的方法。该反应的优点是其良好的官能团耐受性和温和的反应条件。在实验观察的基础上,提出了合理的反应机理。
Chemoselective Synthesis of 3-Bromomethyloxindoles via Visible-Light-Induced Radical Cascade Bromocyclization of Alkenes
A novel visible-light-induced radical cascade bromocyclization of N-arylacrylamides has been accomplished. This reaction overcomes the overbromination at the benzene rings suffered in traditional electrophilic reactions, thus enabling the first highly chemoselective synthesis of valuable 3-bromomethyloxindoles. The combination of pyridine and anhydrous medium is identified as the key factor for the