1: 92 percent / thionyl chloride / 18 h / Ambient temperature 2: 100 percent / CH2Cl2 / 0.5 h / 0 °C 3: 92 percent / thionyl chloride / 1 h 4: 1.) n-BuLi / 1.) ethyl ether, 0 deg C, 1 h, 2.) RT, overnight View Scheme

1: 100 percent / CH2Cl2 / 0.5 h / 0 °C 2: 92 percent / thionyl chloride / 1 h 3: 1.) n-BuLi / 1.) ethyl ether, 0 deg C, 1 h, 2.) RT, overnight View Scheme

1: 92 percent / thionyl chloride / 1 h 2: 1.) n-BuLi / 1.) ethyl ether, 0 deg C, 1 h, 2.) RT, overnight View Scheme

n-butyllithium 1.) ethyl ether, 0 deg C, 1 h, 2.) RT, overnight; Yield given. Multistep reaction;