1: 2-pentyl[1,3]dithiane With n-butyllithium in tetrahydrofuran; hexane T=0°C; 0.5 h; 2: chloro-trimethyl-silane in tetrahydrofuran; hexane T=20°C; 1.5 h;

1.1: 96 percent / BF3*OEt2 / CH2Cl2 / 26 h / 20 °C 2.1: n-BuLi / tetrahydrofuran; hexane / 0.5 h / 0 °C 2.2: 92 percent / tetrahydrofuran; hexane / 1.5 h / 20 °C View Scheme

1: 68 percent / methyl iodide; CaCO3; H2O / acetonitrile / 16 h / 55 °C 2: 87 percent / DIBALH / CH2Cl2; toluene / 1.17 h / -78 - 0 °C 3: 92 percent / saccharin / CH2Cl2 / 24 h / 40 °C View Scheme

1: 68 percent / methyl iodide; CaCO3; H2O / acetonitrile / 16 h / 55 °C 2: 87 percent / DIBALH / CH2Cl2; toluene / 1.17 h / -78 - 0 °C View Scheme

water; calcium carbonate; methyl iodide in acetonitrile T=55°C; 16 h;