Phosgene → HCID 12805020, compound

Participants

Reaction Steps

3.2 g (44.4 millimoles) of (hydroxymethyl)cyclopropane, dissolved in 50 ml of absolute ether, are added dropwise to a stirred solution of 8.8 g (89.0 millimoles) of phosgene in 50 ml of absolute ether at 10°-15° C. The reaction solution is then stirred for 3 hours at room temperature. The excess phosgene is removed by means of a dry stream of nitrogen, and the ether is then removed under reduced pressure at room temperature. The cyclopropylmethyl chloroformate which remains is mixed with 6.0 g (29.5 millimoles) of 6-(p-aminophenyl)-4,5-dihydro-5-methyl-3(2H)-pyridazinone and 100 ml of absolute toluene and the mixture is kept for 7 hours at 80° C. The product is filtered off at 10° C., washed first with toluene and then with water, and recrystallized twice from dimethylformamide/water. 3.0 g (34% of theory) of 6-(p-cyclopropylmethoxycarbonylaminophenyl)-4,5-dihydro-5-methyl-3(2H)-pyridazinone are obtained as colorless crystals of melting point 240°-241° C.

Provenance & Evidence