tetrafluoroboric acid; KNO2 T=5°C; 1 h;

1: 1.) p-toluenesulfonic acid, 2.) ethanolic NH3 / 1.) a) RT, 10 min, b) 120 deg C, 15 min, 2.) 90 deg C, 16 h 2: 89 percent / m-chloroperoxybenzoic acid / ethanol / 19 h / Ambient temperature 3: 85 percent / NH3 / 48 h / Ambient temperature 4: 21 percent / 48percent aq. HBF4, KNO2 / 1 h / 5 °C View Scheme

1: 85 percent / NH3 / 48 h / Ambient temperature 2: 21 percent / 48percent aq. HBF4, KNO2 / 1 h / 5 °C View Scheme