One-pot synthesis of some new semicarbazone, thiosemicarbazone, and hydrazone derivatives of 1-phenyl-3-arylpyrazole-4-carboxaldehyde from acetophenone phenylhydrazones using Vilsmeier-Haack reagent
Semicarbazone derivatives 3 of 1,3-diphenylpyrazole-4-carboxaldehyde have been synthesized in high yields through a one-pot procedure involving acetophenone phenylhydrazones 1 subjected to Vilsmeier double formylation and workup under new conditions (i.e., treatment with semicarbazide followed by sodium bicarbonate). This method is even suitable for preparing other derivatives (i.e., thiosemicarbazones 4 and hydrazones 5) in high yields. Copyright Taylor & Francis Group, LLC.
Pundeer, Rashmi,Ranjan, Pooja,Pannu, Kamaljeet,Prakash, Om