反应详情

2.8 l of o-toluidine and 2.5 l of pyridine are added to 50 l of dichloromethane at 3° C. 13.6 kg of 2,4-bisbenzyloxy-5-bromobenzoyl chloride (toluene-moist) suspended in 35 l of dichloromethane are added to this solution over the course of 2 h. The mixture is subsequently stirred overnight at 23° C., and the solid is filtered off and rinsed with dichloromethane (2× with 5 l each time). The crude product obtained in this way (8 kg) is dissolved in 40 l of dichloromethane and extracted successively with 40 l of distilled water, 50 l of hydrochloric acid (˜1 mol/l; prepared from 5 l of HCl w: 37% and 50 l of water). The organic phase is subsequently washed with 50 l of water. The organic phase is dried for 3 days using 6 kg of sodium sulfate. The drying agent is filtered off with suction via a suction filter, and the filtrate is evaporated to dryness in a rotary evaporator. Recrystallisation from ethanol (35 l, 65° C.) and drying (50° C./35 mbar) to constant weight gives 10.84 kg (82%) of 2,4-bisbenzyloxy-5-bromo-N-o-tolylbenzamide (m.p. 174.5° C.-176° C.; MW 502.4).

1. additionare added to this solution over the course of 2 h
2. filtrationthe solid is filtered off
3. washrinsed with dichloromethane (2× with 5 l each time)
4. customThe crude product obtained in this way (8 kg)
5. extractionextracted successively with 40 l of distilled water, 50 l of hydrochloric acid (˜1 mol/l; prepared from 5 l of HCl w: 37% and 50 l of water)
6. washThe organic phase is subsequently washed with 50 l of water
7. customThe organic phase is dried for 3 days
8. filtrationThe drying agent is filtered off with suction via a suction
9. filtrationfilter
10. customthe filtrate is evaporated to dryness in a rotary evaporator
11. customRecrystallisation from ethanol (35 l, 65° C.)
12. customdrying (50° C./35 mbar) to constant weight