1: With sodium chlorate; sodium dihydrogenphosphate; dihydrogen peroxide in water; acetonitrile T=0 - 20°C; 3.5 h; 2: With sodium sulfite in water; acetonitrile T=20°C; 0.25 h; 3: With hydrogenchloride in water; acetonitrile pH=3;

bromine in chloroform T=0 - 20°C;