Aromatic nucleophilic substitution reactions of activated N-arylpyrazoles with formamides

Different activated N-arylpyrazoles, as N-(2',4'-dinitrophenyl)-3,5-dimethylpyrazole, N-picryl-3-5-dimethylpyrazole etc., can react with excess formamides, as formamide N-methylformamide and N,N-dimetylformamide, at 165-175 degrees C, for 5-6 hours, resulting amines in high yields. This reaction is influenced by steric hindrance.