toluene-4-sulfonic acid in Petroleum ether 120 h; Heating;

1: 41 percent / NaN3, MgCl2*6H2O / methanol / 120 h / Heating 2: 85 percent / p-toluenesulfonic acid / benzene / 12 h / Heating 3: 59 percent / P(OEt)3 / CH2Cl2 / 40 h / Heating 4: 98 percent / p-toluenesulfonic acid / diethyl ether; H2O / 0.5 h / Ambient temperature 5: 43 percent / 1.) isopentylnitrite, triethylamine / 1.) 30 min; 2.) CCl4, 80 deg C, 30 min 6: 75 percent / p-toluenesulfonic acid / benzene / 12 h / Heating View Scheme

lithium chloride in water; dimethyl sulfoxide T=90°C; 6 h;