반응 #441426

반응 방정식

hydroxylamine hydrochloride

sodium hydride

2-chloro-5-trifluoromethylpyridine

3-Chloro-4-fluoroacetophenone

sodium hydroxide

→

title compound

수율 85.0%

1-(3-Chloro-4-fluorophenyl)-2-(5-trifluoromethyl-2-pyridinyl)ethanone Oxime

수율 85.0%

용매

water

DME

DME

methanol

반응 조건

후처리

1. 1
   기타at 40-45° C.
2. 2
   기타overnight
3. 3
   기타Upon the completion of the reaction
4. 4
   온도the mixture was cooled to 5° C.
5. 5
   온도The mixture was heated to 72° C. for 4 hours
6. 6
   온도then cooled
7. 7
   workup.STIRRINGwith stirring
8. 8
   기타The resulting solid was removed by filtration
9. 9
   기타dried under vacuum
10. 10
    여과then filtered
11. 11
    세척washing with further cyclohexane
12. 12
    기타The crude solid was purified by dissolution in diethylether (50 ml)
13. 13
    세척passage through silica gel, washing with further diethylether

실험 절차

A reaction vessel was charged with sodium hydride (as a 60% oil dispersion, 7.2 g, 180 mmol), DME (60 ml) and 2-chloro-5-trifluoromethylpyridine (10 g, 55.1 mmol). 3-Chloro-4-fluoroacetophenone (9.8 g, 56.9 mmol) in DME (20 ml) was added in portions to the mixture under nitrogen at room temperature. The mixture was stirred at ambient temperature for one hour then at 40-45° C. overnight. Upon the completion of the reaction, the mixture was cooled to 5° C. and 10% aqueous sodium hydroxide solution (30 ml) was slowly added to the reaction mixture followed by methanol (60 ml) then hydroxylamine hydrochloride (19.1 g, 357 mmol). The mixture was heated to 72° C. for 4 hours then cooled and diluted with water (1500 ml) with stirring. The resulting solid was removed by filtration and dried under vacuum. It was then slurried in cyclohexane (100 ml) then filtered, washing with further cyclohexane. The crude solid was purified by dissolution in diethylether (50 ml) and passage through silica gel, washing with further diethylether. Concentration of the filtrate afforded 15.56 g (85%) of the title compound.

출처