反应详情

温度

55 °C

In 37.8 kg of 88% formic acid was dissolved 7.5 kg (91% pure, 36.37 mole) of 1-(4-pyridyl)-1,3-diketo-2-oximinopentane and 7.0 kg of methanesulfonic acid. The resulting solution was slowly added to a slurry of 8.3 kg of zinc powder in 35.7 kg of formic acid. The reaction temperature was kept at about 60° C. by proper cooling and slow addition. The mixture was allowed to stir at 55° C. for 2 hours and then cooled to 20° C. The solid zinc formate was filtered off. To the formic acid filtrate was added 3.6 kg of methanesulfonic acid. The formic acid was removed at the reduced pressure (40 mm Hg) and 70° C. To the residue was added a solution of 5.9 kg of methanol and 53.3 kg of isopropanol and stirred at 20° C. for 4 hours. Solid material was collected by centrifugation, washed with 12.5 kg of 10% methanol in isopropanol giving 11.0 kg, 87% yield, of the title compound as dimethanesulfonate salt after drying.

1. customwas kept at about 60° C.
2. temperatureby proper cooling
3. additionslow addition
4. temperaturecooled to 20° C
5. filtrationThe solid zinc formate was filtered off
6. additionTo the formic acid filtrate was added 3.6 kg of methanesulfonic acid
7. customThe formic acid was removed at the reduced pressure (40 mm Hg) and 70° C
8. additionTo the residue was added a solution of 5.9 kg of methanol and 53.3 kg of isopropanol
9. stirringstirred at 20° C. for 4 hours
10. customSolid material was collected by centrifugation