1: 85 percent / Ph3P, diethylazidoformate, LiBr / tetrahydrofuran / 24 h / Ambient temperature 2: 1.) Mg, 2.) PCl3 / 1.) Et2O, RT, 3 h, ultrasonic irrad., 2.) Et2O, from -78 deg C to RT 3: LiAlH4 / diethyl ether / 0.5 h / Heating View Scheme