反应详情

A mixture of 400 ml of absolute ethanol, 50 ml of water, 72.6 g of zinc dust, 53.3 g of the 2-(difluoromethoxy)-6-methylnitrobenzene, (Example 3A), and a solution of 20.0 g of calcium chloride dissolved in 60 ml of water was refluxed for three hours, allowed to stand overnight, refluxed for an additional hour, and then an additional 43 g of zinc dust and a solution of 18 g of calcium chloride dissolved in 50 ml of water was added. Refluxing for an additional three hours was required to drive the reaction to completion. The reaction was vacuum filtered through Celite®, the filter cake rinsed with 300 ml of ethanol and the filtrate concentrated to a volume of 100 ml. The liquid was diluted with 300 ml of ethyl acetate, 80 ml of 10% sodium hydroxide solution and 100 ml of water. A precipitate formed which was removed by vacuum filtration through Celite. The filter cake was rinsed with 200 ml of ethyl acetate. The phases were separated and the organic phase was dried with sodium sulfate, filtered and concentrated to yield 25.8 g of the desired intermediate as a black oil.

1. temperaturewas refluxed for three hours
2. temperaturerefluxed for an additional hour
3. additionwas added
4. temperatureRefluxing for an additional three hours
5. customthe reaction to completion
6. filtrationfiltered through Celite®
7. washthe filter cake rinsed with 300 ml of ethanol
8. concentrationthe filtrate concentrated to a volume of 100 ml
9. additionThe liquid was diluted with 300 ml of ethyl acetate, 80 ml of 10% sodium hydroxide solution and 100 ml of water
10. customA precipitate formed which
11. customwas removed by vacuum filtration through Celite
12. washThe filter cake was rinsed with 200 ml of ethyl acetate
13. customThe phases were separated
14. dry with materialthe organic phase was dried with sodium sulfate
15. filtrationfiltered
16. concentrationconcentrated