n-butyllithium; substituted 1,2-dibromoethane 1.) THF, -78 deg C - 0.5 h, room temperature - 1 h, 2.) THF, -78 deg C - 1 h, room temperature - 2 h; Yield given. Multistep reaction;

hydrogenchloride 15 h; Heating;

1: aq. HCl / 15 h / Heating 2: 1.) aq. NaHCO3 / 2.) DMF, 0 deg C, 4 h View Scheme