hydrogen; palladium on activated charcoal in ethanol Ambient temperature;

1: 44 percent / 65percent aq. HNO3 / acetic acid / 4 h / 15 - 20 °C 2: 81 percent / H2 / 10percent Pd/C / ethanol / Ambient temperature View Scheme

hydrogen bromide; copper(I) bromide; sodium nitrite 1.) < 5 deg C; 2.) heating, 2 h; Yield given. Multistep reaction;