1: With ethanol; acetic acid; zinc in dichloromethane T=0 - 20°C; 0.5 h; 2: With sodium hydrogencarbonate in water pH=8;

1: 4-(N,N-dimethlyamino)pyridine; copper diacetate / dichloromethane / 12 h / 20 °C 2: nitric acid; acetic acid / 10 - 40 °C 3: zinc; acetic acid / dichloromethane; ethanol / 0.5 h / 20 °C View Scheme

1: nitric acid; acetic acid / 10 - 40 °C 2: zinc; acetic acid / dichloromethane; ethanol / 0.5 h / 20 °C View Scheme

1: T=80°C; 1 h; 2: With toluene-4-sulfonic acid in toluene T=100°C; 3 h;

1.1: 1 h / 80 °C 1.2: pH 9 - 10 1.3: 3 h / 100 °C 2.1: copper(I) oxide; ammonia / ethylene glycol / Sealed tube View Scheme