Synthesis of 1,2,4-thiadiazoles
I2-mediated oxidative C-N and N-S bond formations in water enable a metal-free, environmentally benign and convenient strategy for the synthesis of 4,5-disubstituted/N-fused 3-amino-1,2,4-triazoles and 3-substituted 5-amino-1,2,4-thiadiazoles from isothiocyanates. The scalable protocols exhibited excellent substrate tolerance.
N. Jatangi, N. Tumula, R. K. Palakodety, M. Nakka, J. Org. Chem., 2018, 83, 5715-5723.
An intramolecular oxidative S-N bond formation of imidoyl thioureas mediated by phenyliodine(III) bis(trifluoroacetate) enables an efficient, metal-free synthesis of 3-substituted-5-arylamino-1,2,4-thiadiazoles. The protocol offers broad substrate scope, very short reaction times and very good yields.
A. Mariappan, K. Rajaguru, N. M. Chola, S. Muthusubramanian, N. Bhuvanesh, J. Org. Chem., 2016, 81, 6573-6579.