nitric acid; acetic anhydride T=20°C; 16 h;

1: isopropyl alcohol With sodium hydride in tetrahydrofuran; mineral oil T=0°C; 0.25 h; Inert atmosphere; 2: 3-nitro-4-fluoro-benzoic acid in tetrahydrofuran; mineral oil T=0 - 20°C; 3.5 h; Inert atmosphere;