Janjic, Monika published the artcileA Simple Synthesis of 5-(2-Aminophenyl)-1H-pyrazoles, COA of Formula: C9H9N3, the main research area is aminophenylpyrazole multistep synthesis; pyrazole multistep aminophenyl synthesis; enamino ketone preparation cyclization hydrazine; nitrophenylpyrazole preparation hydrogenation.
A four-step synthesis of 1-substituted 5-(2-aminophenyl)-1H-pyrazoles as a novel type of histamine analog and versatile building blocks for further transformations was developed. The synthesis starts from com. available 2-nitroacetophenone, which is converted into the enamino ketone (E)-2-O2NC6H4COCH:CHNMe2 (I) as the key intermediate. Cyclization of the key intermediate (I) with monosubstituted hydrazines afforded the 5-(2-nitrophenyl)-1H-pyrazoles. Finally, catalytic hydrogenation of the nitro compounds furnished the title compounds in good yields. As demonstrated by some further transformations, addnl. functionalization of 5-(2-nitrophenyl)-1H-pyrazoles and 5-(2-aminophenyl)-1H-pyrazoles is feasible, either by electrophilic substitution at C(4) of the pyrazole ring, or at the NH2 group.
Helvetica Chimica Acta published new progress about Cyclization. 111562-32-4 belongs to class pyrazoles-derivatives, name is 2-(1H-Pyrazol-3-yl)aniline, and the molecular formula is C9H9N3, COA of Formula: C9H9N3.
Referemce:
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics