Dimethylformamide → HCID 86718318, compound

Participants

Reaction Conditions

Reaction Steps

4,5-dichloripyridazine-3(2H)-one (60 g, 364 mmol) and distilled water 350 mL) were stirred at room temperature for 10 minutes. A formaldehyde solution (36%, 70 mL) were added and refluxed for 1.5 hours. The resulting material was cooled down to 5-10° C., and the produced precipitate was filtered, washed with cold water (0-5° C., 200 mL), and dried in the air to obtain N-hydroxymethyl-4,5-dichloropyridazine-3(2H)-one. A methylene chloride solution (50 mL) of thionyl chloride (357 mmol) and dimethyl formamide (360 mmol) was slowly added to a mixture of the N-hydroxymethyl-4,5-dichloropyridazine-3(2H)-one and methylene chloride (550 mL) and methylene chloride (550 mL) at room temperature for 30 minutes with stirring. The mixture was stirred at room temperature for 2 hours. After the mixture was cooled down to 0° C., water (200 mL) was slowly added. The solution was neutralized to pH 6.7-7.4 by using NaHCO3 saturated solution. An organic layer was separated and dried on anhydrous magnesium sulfate. The organic solution was evaporated to concentrated under reduced pressure. The residue was washed with n-hexane (100 mL) to obtain 4,5-dichloro-2-chloromethylpyridazine)-3(2H)-one (71.2 g, 92%). White crystal (diethyl ether/n-hexane=1:5, v/v). mp 69-70° C. TLC (CH2Cl2) Rf=0.65. IR (KBr) 3046, 2984, 1670, 1292, 1122, 964 cm-1; 1H NMR (CDCl3): δ 5.83 (s, 2H), 7.88 ppm (s, 1H); 13C NMR (CDCl3) δ 58.40, 134.87, 137.23, 137.34, 155.58 ppm. Elemental analysis calcd. for C5H3Cl3N2O: C, 28.13; H, 1.42; N, 13.12. Found: C, 28.10; H, 1.41; N, 13.09.

Provenance & Evidence