1: p-toluenesulfonic acid monohydrate / ethanol / 3 h / Ambient temperature 2: 81 percent / TiCl4 / CH2Cl2 3: 71 percent / NaNH2 / benzene 4: 1.) O3; 2.) Zn/CH3COOH / 1.) -78 deg C, 30 min; 2.) room temperature overnight. 5: 73 percent / HCl / acetic acid / 21 h / Ambient temperature 6: 81 percent / SiO2 / CHCl3 / 27 h / 60 °C View Scheme

1: p-toluenesulfonic acid monohydrate / ethanol / 3 h / Ambient temperature 2: 81 percent / TiCl4 / CH2Cl2 3: 71 percent / NaNH2 / benzene 4: 1.) O3; 2.) Zn/CH3COOH / 1.) -78 deg C, 30 min; 2.) room temperature overnight. 5: 73 percent / HCl / acetic acid / 21 h / Ambient temperature 6: Al2O3 / hexane / 24 h / 60 °C View Scheme