1: With hydrogenchloride in water 0.333333 h; 2: With sodium nitrite in water T=0 - 5°C; 3: With hypophosphorous ether in water T=0 - 20°C;

1.1: hydrogenchloride / water / 0.33 h 1.2: 2 h / 0 - 5 °C 1.3: 0 - 20 °C 2.1: tert.-butyl lithium / pentane; tetrahydrofuran / 2 h / -80 - -76 °C 2.2: -80 °C 2.3: pH 1 View Scheme

1.1: hydrogenchloride / water / 0.33 h 1.2: 2 h / 0 - 5 °C 1.3: 0 - 20 °C 2.1: tert.-butyl lithium / pentane; tetrahydrofuran / 2 h / -80 - -76 °C 2.2: -80 °C 2.3: pH 1 3.1: thionyl chloride / toluene / 2 h / Reflux View Scheme

1.1: hydrogenchloride / water / 0.33 h 1.2: 2 h / 0 - 5 °C 1.3: 0 - 20 °C 2.1: tert.-butyl lithium / pentane; tetrahydrofuran / 2 h / -80 - -76 °C 2.2: -80 °C 2.3: pH 1 3.1: thionyl chloride / toluene / 2 h / Reflux 4.1: ammonia / toluene; tetrahydrofuran / 1 h View Scheme