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.
S. Sharma, Pathare, R. S., Maurya, A. K., Dr. Gopal K., Roy, T. Kanchan, Sawant, D. M., and Pardasani, R. T., “Ruthenium Catalyzed Intramolecular C–S Coupling Reactions: Synthetic Scope and Mechanistic Insight”, Organic Letters, vol. 18, pp. 356-359, 2016.