1: 1)nitrosylsulfuric acid, sodium nitrite, 2) cuprous bromide, 48percent hydrobromic acid / 1) acetic acid, 1 - 5 deg C, 20 min, 2) 1 - 5 deg C, 20 min 2: 13 percent / CrO3 / acetic acid / 1 h / 80 °C View Scheme