Categories: C-N Bond Formation >
Synthesis of Cyanamides
A low-temperature metalation of N-substituted 5H-tetrazoles followed by spontaneous cycloreversion at 0°C provides N-metalated cyanamides that can be reacted in situ with a variety of electrophiles. Addition of lithium organometallics to the N,N'-disubstituted cyanamides enables the synthesis of N,N'-disubstituted amidines.
E. Duchamp, S. Hanessian, Org. Lett., 2020, 22, 8487-8491.
In the presence of trichloroisocyanuric acid, triphenylphosphine, and sodium cyanamide, readily available carboxylic acids were converted into N-acylcyanamides in very good yields within some minutes at room temperature under ultrasound irradiation. In addition, N-acyl-substituted imidazolones were readily accessible through guanylation-cyclization of in situ generated N-acylcyanamides.
W. Phakhodee, D. Yamano, M. Pattarawarapan, Synlett, 2020, 31, 703-707.