反应详情

温度

87.5 °C

25.0 g of 4-chloro-3-methylacetophenone and 13.9 g of trichloroisocyanuric acid were suspended in 150 ml of chlorobenzene. A catalytic amount of azobisisobutyronitrile was added thereto, followed by stirring under heating at from 85 to 90° C. for 12 hours. After completion of the reaction, the reaction mixture was cooled to room temperature, and insoluble matters were collected by filtration. The filtrate was washed with an aqueous sodium hydroxide solution and water in this order, and the organic layer was dried over anhydrous magnesium sulfate. The solvent was distilled off under reduced pressure, and the obtained residue, 12.2 g of potassium cyanate and 14.4 g of methanol were added to 150 ml of N,N-dimethylformamide, followed by stirring under heating at 90° C. for 4 hours. After completion of the reaction, water was added to the reaction mixture, extraction with ethyl acetate was carried out, and the organic layer was dried over anhydrous magnesium sulfate. The solvent was distilled off under reduced pressure, and the obtained residue was purified by silica gel column chromatography (Wakogel C-200, eluent: hexane/ethyl acetate=3/1). The obtained crystals were washed with isopropyl ether to obtain 6.0 g of methyl N-(2-chloro-5-acetylbenzyl)carbamate as colorless crystals.

1. customAfter completion of the reaction
2. temperaturethe reaction mixture was cooled to room temperature
3. filtrationinsoluble matters were collected by filtration
4. washThe filtrate was washed with an aqueous sodium hydroxide solution and water in this order
5. dry with materialthe organic layer was dried over anhydrous magnesium sulfate
6. distillationThe solvent was distilled off under reduced pressure
7. additionthe obtained residue, 12.2 g of potassium cyanate and 14.4 g of methanol were added to 150 ml of N,N-dimethylformamide
8. stirringby stirring
9. temperatureunder heating at 90° C. for 4 hours
10. customAfter completion of the reaction, water
11. dry with materialthe organic layer was dried over anhydrous magnesium sulfate
12. distillationThe solvent was distilled off under reduced pressure
13. customthe obtained residue was purified by silica gel column chromatography (Wakogel C-200, eluent: hexane/ethyl acetate=3/1)
14. washThe obtained crystals were washed with isopropyl ether