Dimethylformamide → 2-Amino-3-nitrobenzamide

To a solution of 100 g (0.55 mol) of acid 5 in 600 ml of tetrahydrofuran (THF) and 1 ml of N,N-dimethylformamide (DMF) 131 g (1.1 mol) of thionyl chloride were added. The mixture was stirred under reflux for 4 h and at room temperature for 12 h. The mixture was concentrated to 300 ml and added to a mixture of 1500 g of ice and 1500 ml of ammonia. The mixture was stirred for 3 h at 5° C. The resulting crystals were isolated at 10° C., washed with water, 100 ml of iso-propanol, and 100 ml of MTBE and dried in a vacuum oven at 50° C. Recrystallisation from toluene/MTBE (3/1). Yield: 68%.

1. concentrationThe mixture was concentrated to 300 ml
2. additionadded to a mixture of 1500 g of ice and 1500 ml of ammonia
3. stirringThe mixture was stirred for 3 h at 5° C
4. customThe resulting crystals were isolated at 10° C.
5. washwashed with water, 100 ml of iso-propanol, and 100 ml of MTBE
6. customdried in a vacuum oven at 50° C
7. customRecrystallisation from toluene/MTBE (3/1)

ORD-Eintrag

ord-a37c5488931e447f901f4e151baa8823

Quelldatensatz

uspto-grants-2011_08

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US07994160B2