sulfuric acid in tetrahydrofuran T=25°C; 20 h;

1: 74 percent / 10percent aqueous H2SO4 / tetrahydrofuran / 20 h / 25 °C 2: 59 percent / 1) lithium diisopropylamide 2) acetic anhydride, sodium acetate / tetrahydrofuran / 1) a) 1h -78 deg C b) 3.75h -78 -> 25 deg C 2) 1h reflux 3: 91 percent / toluene / 24 h / 120 °C 4: 97 percent / 1.0N aqueous NaOH / methanol; tetrahydrofuran / 10 h / 25 °C 5: 1) 1N aqueous KOH 2) oxalyl chloride / 1) MeOH, 25 deg C 2) dry benzene, ca.3h, 25 deg C 6: 76 percent / tetrahydrofuran / 1 h / -78 °C 7: 62 percent / m-CPBA / CH2Cl2 / 25 °C 8: 70 percent / lithium aluminum hydride / tetrahydrofuran / 1 h / 0 °C View Scheme