1: 100 mg / ammonium polysulfide / pyridine / 0.02 h 2: 1.) 6N HCl, NaNO2, 2.) CuCl / 1.) 0 - 3 deg C, 10 min, 2.) 50 deg C, 1 h View Scheme

hydrogenchloride; copper(l) chloride; sodium nitrite 1.) 0 - 3 deg C, 10 min, 2.) 50 deg C, 1 h; Yield given. Multistep reaction;