1: petroleum ether / 48 h 2: 70 percent / Ca2CO3 / acetone / 24 h / Ambient temperature View Scheme

1: N-bromosuccinimide (NBS) / CCl4 / 3 h / 70 °C / Irradiation 2: CCl4; methanol / 6 h / 0 °C 3: 1.) NaH / 1.) THF, -10 deg C, 10 min, 2.) RT, 24 h 4: tetrahydrofuran / 48 h / Ambient temperature 5: 64 percent / 6 N HCl / acetic acid / 3 h / 100 °C View Scheme

air in tetrachloromethane T=0°C; 336 h;