Catalyst-free microwave-assisted amination of 2-chloro-5-nitrobenzoic acid.
The synthesis of N-substituted 5-nitroanthranilic acid derivatives 3a-w was achieved by a new, mild, microwave-assisted, regioselective amination reaction of 5-nitro-2-chlorobenzoic acid (1a) with a diverse range of aliphatic and aromatic amines 2a-w without added solvent or catalyst. Up to >99% isolated yield was obtained within 5-30 min at 80-120 degrees C. The reaction, which is suitable for upscaling, yielded new compounds that are of considerable interest as useful building blocks and as potential drugs.
Baqi
Younis
Y
Pharmaceutical Chemistry I, University of Bonn, An der Immenburg 4, D-53121 Bonn, Germany.
Müller
Christa E
CE
D001565:Benzoates / Q000737:chemistry*; D002384:Catalysis; D002723:Chlorobenzoates; D002851:Chromatography, High Pressure Liquid; D009682:Magnetic Resonance Spectroscopy; D008872:Microwaves; D009574:Nitro Compounds / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization; D013056:Spectrophotometry, Ultraviolet
C522946:2-chloro-5-nitrobenzoic acid; D001565:Benzoates; D002723:Chlorobenzoates; D009574:Nitro Compounds