Ethylene Glycol → 2-Amino-5-Chloro-N,3-Dimethylbenzamide

Temperature

2.5 °C

The solution prepared in Step B (96.2 g, 200 mmol) was diluted with acetonitrile (60.0 g) and ethylene glycol (180 g) and dried azeotropically by distilling at atmospheric pressure under a Claisen distillation head to take off ˜72 mL of volatiles. Then the distillation head was replaced with a dry-ice-cooled condenser, the remaining solution was cooled to 0-5° C., and methylamine gas (31.1 g, 1000 mmol) was added below the surface of the reaction mixture. The mixture was heated at 70° C. for 17.5 h, and then water (400 mL) was added slowly to precipitate the product. The mixture was cooled slowly to 5° C., stirred for 15 minutes at this temperature, filtered, and the solids were washed with water and dried under nitrogen to afford the subject compound (36.36 g, 91.5% yield). HPLC showed 99.3 area % purity.

1. customdried azeotropically
2. distillationby distilling at atmospheric pressure under a Claisen distillation head
3. temperaturecooled condenser
4. temperatureThe mixture was heated at 70° C. for 17.5 h
5. customto precipitate the product
6. temperatureThe mixture was cooled slowly to 5° C.
7. filtrationfiltered
8. washthe solids were washed with water
9. customdried under nitrogen

ORD record

ord-39fa8bd4981d4a3db3b931bdd651bfac

Source dataset

uspto-grants-2009_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07528260B2