1: dibenzoyl peroxide; CCl4; N-bromo-succinimide / Irradiation 2: aqueous NaOH View Scheme

in 1,2-dichloro-ethane T=60°C; 3 h;

1: 1.) NaH / 1.) DMF, 30 min, 2.) DMF, a) 75 deg C, 2 h, b) 90 deg C, 3 h 2: 6N HCl / 5 h / Heating 3: 1.) n-BuLi / 1.) THF, hexane, -5 deg C, 2.) THF, hexane, 0 deg C, 2 h View Scheme