sodium hydride in tetrahydrofuran T=20°C; 72 h;

1: 97 percent / H2 / Pd/C / ethyl acetate / 760 Torr 2: 80 percent / DIBAL-H / CH2Cl2; hexane / 30 h / -78 °C 3: 67 percent / KF / propan-2-ol / 20 °C 4: 90 percent / methanesulfonyl chloride; triethylamine / CH2Cl2 / 0.33 h / 0 °C 5: 75 percent / H2O; ethyl acetate / 24 h / 50 - 55 °C View Scheme