acetic anhydride in ethanol; acetic acid

1: 3-trifluoromethyl-aniline With hydrogen bromide; sodium nitrite in water T=-5 - 0°C; 0.5 h; 2: With hydrogen bromide; tin(ll) chloride in water T=0°C; 2 h; 3: mucobromic acid in water T=80 - 90°C;