lithium aluminium tetrahydride in diethyl ether 12 h; Reflux;

1.1: magnesium 1.2: 3.5 h / -78 °C 2.1: lithium aluminium tetrahydride / diethyl ether / 12 h / Reflux View Scheme

1.1: bromine; triphenylphosphine / dichloromethane / 2 h / 0 °C 2.1: magnesium 2.2: 3.5 h / -78 °C 3.1: lithium aluminium tetrahydride / diethyl ether / 12 h / Reflux View Scheme

1.1: oxalyl dichloride; dimethyl sulfoxide / dichloromethane / 0.5 h / -60 °C 1.2: 0.17 h / -60 - 20 °C 2.1: diethyl ether / 12 h / 0 - 20 °C View Scheme