1: 65 percent / DIBAL / toluene / -40 °C 2: 49 percent / Ac2O, NaOAc / acetic acid / 110 °C View Scheme

sodium acetate; acetic anhydride; diisobutylaluminium hydride; acetic acid 1.) CH2Cl2, -90 deg C, 2.) 110 deg C, 2 h; Yield given. Multistep reaction;