[N+:1]([C:4]1[O:8][C:7]([C:9]2[C:13]([C:14]#[N:15])=[CH:12][NH:11][N:10]=2)=[CH:6][CH:5]=1)([O-:3])=[O:2].[H-].[Na+].CI.[C:20](O)(=O)C>CN(C)C=O.O>[CH3:20][N:11]1[CH:12]=[C:13]([C:14]#[N:15])[C:9]([C:7]2[O:8][C:4]([N+:1]([O-:3])=[O:2])=[CH:5][CH:6]=2)=[N:10]1
Add 15.4 g of 3-(5-nitro-2-furyl)-1H-pyrazole-4-carbonitrile portionwise to a suspension of 2.5 g of sodium hydride (80% in liquid paraffin) in 90 ml of dimethylformamide while stirring and under nitrogen at from -2° C to -5° C. Stir the thus-obtained reaction mixture for 30 minutes and then add dropwise thereto a solution of 11.8 g of methyl iodide in 20 ml of dimethylformamide. After stirring for 30 minutes, admix therewith 0.6 g of glacial acetic acid and stir the resulting solution into 220 g of ice and water. Remove formed precipitate by vacuum filtration and recrystallize residue twice from dimethylformamide and water. Dry the residue in vacuo. Recrystallize the resulting 13.5 g of product three more times from dimethylformamide and water to obtain a 57% yield of 1-methyl-3-(5-nitro-2-furyl)pyrazole-4-carbonitrile [m.p. 176.5° to 177.5° C].
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