1: Grubbs' catalyst / CH2Cl2 / 12 h 2: Et3N; DMAP / CH2Cl2 / 16 h / 20 °C 3: Na2HPO4; mCPBA / CH2Cl2 / 21 h / 20 °C 4: i-Pr2NEt / CH2Cl2 / 9 h 5: 96 percent / TBAF / tetrahydrofuran / 1 h / 20 °C 6: Jones' reagent / acetone / 0.17 h / 0 °C 7: CH2Cl2; diethyl ether / 0 °C 8: DBU / benzene / 0.5 h / 20 °C 9: 83 percent / AcCl / methanol / 16 h / 20 °C View Scheme