反应详情

To a solution of 3,4-dihydro-3-amino-2H-benzopyran (0.9 g, 6 mmole) in 50 ml of ethyl acetate, there was added 1.22 g (6 mmol) of 2,6-bis(1-methylethyl)phenyl isocyanate. The resulting mixture was stirredat room temperature for twenty hours. The solvent was removed under vacuum and the residue was suspended in 20% ethyl acetate/hexane. The precipitated solid was collected by filtration and dried to yield 1.25 g of N-[2,6-bis(1-methylethyl)phenyl]-N'-(3,4-dihydro-2H-benzopyran-3-yl)urea, mp 186°-188° C.

1. waitThe resulting mixture was stirredat room temperature for twenty hours
2. customThe solvent was removed under vacuum
3. filtrationThe precipitated solid was collected by filtration
4. customdried