hydrogenchloride in ethanol 16 h; Heating;

1: 1) n-BuLi / 1a) Et2O, cyclohexane, 0 deg C, 1h, 1b) RT, 30 min, 2a) 1h, 0 deg C, 2b) 1h, RT 2: 90 percent / p-TsOH / methanol / Ambient temperature 3: NEt3 / CH2Cl2 / 1) 0 deg C, 30 min, 2) RT, 2h 4: 73 percent / LiBr / tetrahydrofuran / 2 h / Heating 5: 1) Mg / 1) Et2O, 2) Et2O, RT, overnight 6: 90 percent / Bu4NF / tetrahydrofuran / 0.17 h / Ambient temperature 7: p-TsOH / methanol / 10 h / Ambient temperature View Scheme