反应详情

In a 20 L autoclave, 1395 g (6 mole) of N-(4-chloro-2-fluoro-5-nitrophenyl)acetamide and 14 g of Ir-catalyst (5% on carbon, 1% w/w) were suspended in 14 L of ethyl acetate. The autoclave was purged two times with nitrogen at 500 kPa (5 atmospheres) pressure followed by purging with hydrogen at 500 kPa (5 atmospheres). 400 kPa (4 atmospheres) pressure of hydrogen was applied for the hydrogenation and the mixture was heated. At 40° C. hydrogen uptake was accompanied by an exotherm. The temperature was allowed to rise to 75-83° C. The hydrogen uptake was complete after 90 minutes. The reactor was stirred an additional 45 minutes at this temperature and cooled to room temperature. The catalyst was removed by filtration through Celite®. After removal of the solvent at reduced pressure, 1165.5 g of the title compound (95.9%) was obtained as a crystalline solid melting at 142-143° C. (purity: >99.5% by HPLC).

1. customThe autoclave was purged two times with nitrogen at 500 kPa (5 atmospheres) pressure
2. customby purging with hydrogen at 500 kPa (5 atmospheres)
3. temperaturethe mixture was heated
4. customAt 40° C.
5. customto rise to 75-83° C
6. customThe catalyst was removed by filtration through Celite®
7. customAfter removal of the solvent at reduced pressure