《Synthesis of unsymmetrical urea from aryl- or pyridyl carboxamides and aminopyridines using PhI(OAc)2via in situ formation of aryl- or pyridyl isocyanates》 was published in New Journal of Chemistry in 2021. These research results belong to Laha, Joydev K.; Singh, Neha; Hunjan, Mandeep Kaur. COA of Formula: C5H5BrN2 The article mentions the following:
A tandem synthesis of unsym. ureas (N-aryl-N’-pyridylurea and N,N’-bipyridylurea) from aryl- or pyridyl carboxamides and aminopyridines via Hofmann rearrangement has been reported. In particular, benzamides, picolinamide, nicotinamide, and isonicotinamide generate reactive intermediate isocyanates, in situ, in the presence of PhI(OAc)2, which upon further reaction with aminopyridines form urea derivatives As the formation of pyridylisocyanates from their corresponding carboxamides via Hofmann rearrangement remained unexplored previously, attempts have been made to trap the isocyanates. While the three pyridylisocyanates were trapped as their corresponding carbamates, 3-pyridylisocyanate was isolated and characterized. Unlike closely related previous methods reported for urea synthesis, the current method avoids direct use of isocyanates or eliminates the use of toxic phosgene for the in situ generation of isocyanates. In the experimental materials used by the author, we found 2-Bromopyridin-3-amine(cas: 39856-58-1COA of Formula: C5H5BrN2)
2-Bromopyridin-3-amine(cas: 39856-58-1) belongs to anime. Large quantities of aliphatic amines are made synthetically. The most widely used industrial method is the reaction of alcohols with ammonia at a high temperature, catalyzed by metals or metal oxide catalysts (e.g., nickel or copper). Mixtures of primary, secondary, and tertiary amines are thereby produced.COA of Formula: C5H5BrN2