Ruthenium Catalyzed Intramolecular C–S Coupling Reactions: Synthetic Scope and Mechanistic Insight

A ruthenium catalyzed intramolecular C–S coupling reaction of N-arylthioureas for the synthesis of 2-aminobenzo­thiazoles has been developed. Kinetic, isotope labeling, and computational studies reveal the involvement of an electrophilic ruthenation pathway instead of a direct C–H activation. Stereoelectronic effect of meta-substituents on the N-arylthiourea dictates the final regioselective outcome of the reaction.本研究开发了一种钌（ruthenium）催化N-芳基硫脲发生分子内C–S偶联反应以合成2-氨基苯并噻唑的方法。动力学、同位素标记及计算化学研究表明，该反应遵循亲电钌化路径，而非直接C–H活化路径。N-芳基硫脲上间位取代基的立体电子效应决定了反应最终的区域选择性结果。