1: With (+)-10-camphorsulfonic acid in methanol T=0°C; 2 h; 2: With manganese(IV) oxide in dichloromethane T=20°C; 14 h;

1.1: LDA / tetrahydrofuran; hexane / 0.33 h / -20 °C 1.2: 85 percent / tetrahydrofuran; hexane / 0.17 h / -78 °C 2.1: imidazole / CH2Cl2 / 0.33 h / 0 °C 3.1: 4.00 g / N-iodosuccinimide; AgNO3 / acetone / 3.5 h / 0 °C 4.1: BH3*SMe2; cyclohexene / diethyl ether / 1 h / 0 °C 4.2: 82 percent / glacial AcOH / diethyl ether / 0.5 h / 0 °C 5.1: (1S)-(+)-10-camphorsulfonic acid / methanol / 2 h / 0 °C 5.2: 75 percent / MnO2 / CH2Cl2 / 14 h / 20 °C View Scheme

1.1: imidazole / CH2Cl2 / 0.33 h / 0 °C 2.1: 4.00 g / N-iodosuccinimide; AgNO3 / acetone / 3.5 h / 0 °C 3.1: BH3*SMe2; cyclohexene / diethyl ether / 1 h / 0 °C 3.2: 82 percent / glacial AcOH / diethyl ether / 0.5 h / 0 °C 4.1: (1S)-(+)-10-camphorsulfonic acid / methanol / 2 h / 0 °C 4.2: 75 percent / MnO2 / CH2Cl2 / 14 h / 20 °C View Scheme

1.1: 4.00 g / N-iodosuccinimide; AgNO3 / acetone / 3.5 h / 0 °C 2.1: BH3*SMe2; cyclohexene / diethyl ether / 1 h / 0 °C 2.2: 82 percent / glacial AcOH / diethyl ether / 0.5 h / 0 °C 3.1: (1S)-(+)-10-camphorsulfonic acid / methanol / 2 h / 0 °C 3.2: 75 percent / MnO2 / CH2Cl2 / 14 h / 20 °C View Scheme

1.1: BH3*SMe2; cyclohexene / diethyl ether / 1 h / 0 °C 1.2: 82 percent / glacial AcOH / diethyl ether / 0.5 h / 0 °C 2.1: (1S)-(+)-10-camphorsulfonic acid / methanol / 2 h / 0 °C 2.2: 75 percent / MnO2 / CH2Cl2 / 14 h / 20 °C View Scheme