Hydrochloric Acid → 4-Chloro-2-(phenylamino)benzoic acid

Temperatur

135 °C

To a solution of 2-bromo-4-chlorobenzoic acid (25.0 g, 106.0 mmol) in 2-ethoxyethanol (40 mL) was added copper powder (0.74 g, 11.6 mmol), copper (I) oxide (0.76 g, 5.3 mmol), potassium carbonate (15.8 g, 114.0 mmol) at room temperature under nitrogen. After stirring for 5 min., aniline (11.2 mL, 124 mmol) was added to the reaction mixture. The reaction mixture was heated at 135° C. for 48 hr. Completion of the reaction was confirmed by silica TLC (mobile phase; hexane:ethyl acetate=1:1; Rf=0.6). The reaction mixture was cooled to room temperature, poured into water (30 mL) with continuous shaking and was acidified with aqueous 1N HCl to form a precipitate. The mixture was stirred overnight at room temperature. The mixture was filtered through a sintered glass funnel. The solids were washed with water (2×100 mL). The obtained solids were dried under high vacuum to yield 4-chloro-2-phenylamino-benzoic acid (19.0 g, 72.3% crude yield). The crude product was used in the next step without further purification. MS calcd. for C13H10ClNO2 [(M+H)+] 247, obsd. 248.

1. temperatureThe reaction mixture was cooled to room temperature
2. stirringwith continuous shaking
3. customto form a precipitate
4. stirringThe mixture was stirred overnight at room temperature
5. filtrationThe mixture was filtered through a sintered glass funnel
6. washThe solids were washed with water (2×100 mL)
7. customThe obtained solids were dried under high vacuum

ORD-Eintrag

ord-7ea6a7c86e68421298eaa6618c2fac53

Quelldatensatz

uspto-grants-2013_08

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08501732B2