1: I2 2: 1.) NaNO2, 3N HCl; 2.) NaOAc / 1.) water, 0 deg C; 2.) water, ethanol, 2 h View Scheme

hydrogenchloride; sodium acetate; sodium nitrite 1.) water, 0 deg C; 2.) water, ethanol, 2 h; Yield given. Multistep reaction;