1.1: ozone / CH2Cl2 / 1 h / -78 °C 1.2: 69 percent / Me2S / CH2Cl2 / 1 h / -78 - 20 °C 2.1: 91 percent / KMnO4; phosphate buffer / 2-methyl-propan-2-ol; H2O / 0.5 h / 20 °C / pH 7 3.1: NEt3; phenyl dichlorophosphate / tetrahydrofuran / 1 h / 0 °C 3.2: 72 percent / NEt3 / tetrahydrofuran / 0.5 h / 0 °C 4.1: 86 percent / trifluoroacetic acid; water / 0.5 h / 20 °C 5.1: 84 percent Spectr. / Bu3SnH / methanol / 3 h / 20 °C / Photolysis View Scheme