Hexamethylenetetramine → 1-Methyl-3-(5-nitrofuran-2-yl)-1H-pyrazole-4-carbaldehyde

Participants

Reaction Steps

Heat 1.0 g of 1-methyl-3-(5-nitro-2-furyl)pyrazole together with 0.73 g of hexamethylenetetramine and 11.6 g of trifluoroacetic acid for 4.5 hours at boiling point. Add the resulting 4-pyrazolylmethyleneammonium-salt-containing solution to 31 ml of ice water. Stir the thus-obtained admixture for 15 minutes, and make it alkaline with concentrated sodium carbonate solution. Filter off the precipitate and wash it with water until it is neutral to obtain 1-methyl-3-(5-nitro-2-furyl)pyrazole-4-carboxaldehyde [melting point: 181° to 182° C] with a yield of 79%.

Provenance & Evidence