3-(3-Chloropropoxy)-4-methoxy-6-nitrobenzoic acid → 2-Amino-4-methoxy-5-(3-chloropropoxy)benzoic acid

Temperature

40 °C

In a 50 mL volume glass flask equipped with a stirrer, a thermometer, a reflux condenser and a gas inlet were placed 4.00 g (13.5 mmol) of 4-methoxy-5-(3-chloropropoxy)-2-nitrobenzoic acid (purity: 99%) obtained in Reference Example III-14, and 40 mL of methanol. The resulting mixture was heated to 40° C. under stirring. To the mixture was added 0.4 g of 5 wt. % palladium/carbon (containing 49% water) at the same temperature. The resulting mixture was heated to the same temperature for 4 hours, while hydrogen was introduced into the mixture under atmospheric pressure at a rate of 50 mL/min. After the reaction was complete, the reaction mixture was filtered and the filtrate was concentrated under reduced pressure, to precipitate a crystalline product. The crystalline product was dried under reduced pressure, to give 3.52 g (isolated yield: 98.1%, purity: 98% in terms of area percentage determined by high performance liquid chromatography) of 4-methoxy-5-(3-chloropropoxy)-anthranilic acid as a white crystalline product.

1. customIn a 50 mL volume glass flask equipped with a stirrer
2. additionwas introduced into the mixture under atmospheric pressure at a rate of 50 mL/min
3. filtrationthe reaction mixture was filtered
4. concentrationthe filtrate was concentrated under reduced pressure
5. customto precipitate a crystalline product
6. customThe crystalline product was dried under reduced pressure

ORD record

ord-e3ef8998eba54c41bd3c0b6ab427ed7d

Source dataset

uspto-grants-2013_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08367824B2