Trifluoroacetic anhydride → Benzoic acid, 4-[methyl(trifluoroacetyl)amino]-

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

4-(N-Methyltrifluoroacetamido)benzoic acid may be prepared in the following manner: a solution of trifluoroacetic anhydride (43.75 g) in anhydrous diethyl ether (50 cc) is added to a solution of 4-methylaminobenzoic acid (21 g) in anhydrous diethyl ether (200 cc) while the temperature is maintained in the vicinity of 0° C. The reaction mixture is then stirred for 20 hours at a temperature in the region of 20° C. and is thereafter concentrated to dryness under reduced pressure (2.7 kPa). On recrystallization of the residue obtained in a diisopropyl ether/ethyl acetate mixture (80:20 by volume), 4-(N-methyltrifluoroacetamido)benzoic acid (7.5 g), m.p. 175° C., is obtained.

Herkunft & Nachweise