Triethylamine → N-Cyclopropyl-N'-(2-fluoro-4-iodophenyl)urea

Participants

Reaction Steps

Under a nitrogen atmosphere, to N,N-carbonyldiimidazole (82.1 g) were added N,N-dimethylformamide (400 ml) and triethylamine (70.5 ml), and a solution of 2-fluoro-4-iodoaniline 47 (100 g) in N,N-dimethylformamide (100 ml) was added dropwise under ice-cooling. After the completion of the dropwise addition, the mixture was stirred at room temperature for 5 hrs. The reaction mixture was ice-cooled, and cyclopropylamine (44.0 ml) was added dropwise. The mixture was stirred at room temperature for 1 hr, and the reaction mixture was added dropwise to water-toluene [2:1 (volume ratio), 1500 ml] with stirring. The precipitated crystals were collected by filtration and dried to give 1-cyclopropyl-3-(2-fluoro-4-iodo-phenyl)-urea 48 (129 g, yield 95.5%) as colorless crystals.

Provenance & Evidence