Chlorodifluoromethane → 1-Bromo-2-(difluoromethoxy)-3-nitrobenzene

Temperature

80 °C

Into a 200-ml four-necked flask provided with a reflux condenser, a stirrer and a thermometer were fed 4.36 g (0.02 mol) of 2-bromo-6-nitrophenol, 16.7 g (0.1 mol) of 24% sodium hydroxide, 20 ml of 1,4-dioxane and 7 ml of water. The mixture was heated to 80° C. The mixture was stirred at that temperature for 11 hours with heating while chlorodifluoromethane (flon 22) was blown thereinto from a bomb. The reaction mixture was cooled and then subjected to extraction two times each using 20 ml of ether. The ether layer was washed with 20 ml of 12% sodium hydroxide and then with the same volume of water. Then, the ether layer was dried over anhydrous sodium sulfate and then subjected to distillation to obtain 1.79 g of 3-bromo-2-difluoromethoxynitrobenzene (yield: 33.4%, purity: 98.8%). To the sodium hydroxide washing was added hydrochloric acid to make the washing acidic, and the resulting precipitate was subjected to extraction with ether, to recover 2.2 g of unreacted 2-bromo-6-nitrophenol (recovery ratio: 50%).

1. customInto a 200-ml four-necked flask provided with a reflux condenser, a stirrer
2. temperatureThe reaction mixture was cooled
3. extractionsubjected to extraction two times each using 20 ml of ether
4. washThe ether layer was washed with 20 ml of 12% sodium hydroxide
5. dry with materialThen, the ether layer was dried over anhydrous sodium sulfate
6. distillationsubjected to distillation

ORD record

ord-e639ef9c534a47b1a580cee1fda9aec1

Source dataset

uspto-grants-2001_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06316658B1