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

A ruthenium catalyzed intramolecular C–S coupling reaction of <i>N</i>-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 <i>N</i>-arylthiourea dictates the final regioselective outcome of the reaction

Sequential Pd(0)/Fe(III) Catalyzed Azide–Isocyanide Coupling/Cyclization Reaction: One-Pot Synthesis of Aminotetrazoles

A rapid and efficient synthesis of aminotetrazole from aryl azides, isocyanides, and TMSN₃ is developed. The reaction is promoted by sequential Pd(0)/Fe­(III) catalysis. The reaction sequence utilizes the Pd-catalyzed azide–isocyanide denitrogenative coupling reaction to generate unsymmetric carbodiimide <i>in situ</i>, which reacts with TMSN₃ in the presence of FeCl₃ in a single pot. The methodology has distinct advantages over traditional synthetic approaches where toxic Hg and Pb salts are employed at stoichiometric scale

Sequential Pd(0)/Fe(III) Catalyzed Azide–Isocyanide Coupling/Cyclization Reaction: One-Pot Synthesis of Aminotetrazoles

A rapid and efficient synthesis of aminotetrazole from aryl azides, isocyanides, and TMSN₃ is developed. The reaction is promoted by sequential Pd(0)/Fe­(III) catalysis. The reaction sequence utilizes the Pd-catalyzed azide–isocyanide denitrogenative coupling reaction to generate unsymmetric carbodiimide <i>in situ</i>, which reacts with TMSN₃ in the presence of FeCl₃ in a single pot. The methodology has distinct advantages over traditional synthetic approaches where toxic Hg and Pb salts are employed at stoichiometric scale