ethanol T=0°C;

sodium ethanolate in tert-butyl alcohol

hydrogenchloride Heating;

1: 68 percent / p-TsOH / benzene / 5 h / Heating 2: 83 percent / LiCl / H2O; dimethylsulfoxide / 3 h / Heating 3: 1.) LDA / 1.) hexane, THF, -70 deg C, 1 h; 2.) HMPA, THF, r.t., 1 h 5: 3 percent / CCl4 / 3 h / 50 °C View Scheme

toluene-4-sulfonic acid in benzene 5 h; Heating;