1: 88 percent / LAH / tetrahydrofuran / 1.5 h / Heating 2: 88 percent / triethyl amine / CH2Cl2 / 2 h / 20 °C 3: 51 percent / PPh3; DIAD / tetrahydrofuran / 24 h 4: 70 percent / TFA / CHCl3 View Scheme

1: 88 percent / LAH / tetrahydrofuran / 1.5 h / Heating 2: 88 percent / triethyl amine / CH2Cl2 / 2 h / 20 °C 3: 51 percent / PPh3; DIAD / tetrahydrofuran / 24 h 4: 70 percent / TFA / CHCl3 View Scheme

lithium aluminium tetrahydride in tetrahydrofuran 1.5 h; Heating;