1.1: NaNO2; 37 percent HCl / H2O / 1.5 h / 5 °C 1.2: 47 percent / NaN3; NaOAc / H2O / 1 h / 0 - 5 °C 2.1: 73 percent / 1,2-dichloro-benzene / 1 h / Heating View Scheme