反应详情

3,5-Dichloro-4-methoxyaniline (1.8 g) and diethylaniline (1.5 g) were dissolved in benzene (20 ml). To the resultant solution was dropwise added isopropyl chloroformate (1.2 g) in 5 minutes under ice-cooling. After being allowed to stand at room temperature for 12 hours, the reaction mixture was poured into ice-water and extracted with ethyl acetate. The extract was washed with water, dried over magnesium sulfate and concentrated under reduced pressure. The residue was purified by silica gel chromatography using a mixture of benzene and tetrahydrofuran as the eluent to give isopropyl N-(3,5-dichloro-4-methoxyphenyl)carbamate (Compound No. 2) (2.4 g) in a yield of 91.8%. M.P., 107.5°-108° C.

1. customin 5 minutes
2. temperaturecooling
3. extractionextracted with ethyl acetate
4. washThe extract was washed with water
5. dry with materialdried over magnesium sulfate
6. concentrationconcentrated under reduced pressure
7. customThe residue was purified by silica gel chromatography
8. additiona mixture of benzene and tetrahydrofuran as the eluent