反应详情

Potassium t-butoxide (239.7 g, 2.136 mol) was dissolved in t-butanol (1.5 liters) and allowed to stir at room temperature for 30 minutes. 2,3-Dichloroacetophenone (67.26 g, 0.356 mol) was added in one portion and the resulting mixture stirred overnight at room temperature. Amyl nitrite (83.41 g, 0.712 mol) was added slowly dropwise, with stirring. When the addition was complete the reaction mixture was stirred at room temperature for 2 hours and then heated at 50° C. for 2 hours. The solution was allowed to cool and stirred at room temperature overnight. The reaction mixture was poured into ice/water (1.5 liters), and the aqueous solution extracted with diethyl ether (3×500 ml). The aqueous phase was acidified with concentrated hydrochloric acid and allowed to stand at room temperature overnight. The solid which precipitated was filtered at the pump and dried under vacuum over anhydrous phosphorus pentoxide to give 2,3-dichlorophenylglyoxal aldoxime (57.3 g, 73.8%) as a brown solid. T.l.c. (SiO2 ; CHCl3) showed little impurity, but subsequent dehydration of the oxime showed that recrystallisation would be advisable. The oxime may be recrystallised from toluene, m.p. 109° C.

1. stirringthe resulting mixture stirred overnight at room temperature
2. stirringwith stirring
3. additionWhen the addition
4. stirringwas stirred at room temperature for 2 hours
5. temperatureheated at 50° C. for 2 hours
6. temperatureto cool
7. stirringstirred at room temperature overnight
8. extractionthe aqueous solution extracted with diethyl ether (3×500 ml)
9. waitto stand at room temperature overnight
10. customThe solid which precipitated
11. filtrationwas filtered at the pump
12. dry with materialdried under vacuum over anhydrous phosphorus pentoxide