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

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

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.

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