1: 2,2,2-Trifluoro-N-(2-phenylethyl)acetamide; iodine With sulfuric acid; periodic acid in water; acetic acid T=55 - 70°C; 2 h; 2: in water; acetic acid T=70°C; 2 h; 3: iodine in water; acetic acid T=70°C; 0.5 h;