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

1: 1.) Br2, 48percent HBr / 1.) AcOH, ice-cooling, 30 min, 2.) THF, reflux, 4 h 2: 1.) NaNO2, 40percent H2SO4; 2.) CuSO4.5H2O, NaCl / 1.) water, -12 deg C, 2 h; 2.) water, -2 deg C, 2 h, room temperature 3: 98 percent / hydrogen chloride / ice-cooling 4: 99 percent / H2, triethylamine / 10percent Pd-C / ethanol 5: 78 percent / methanol 6: 88 percent / p-TsOH / toluene / 4 h / Heating View Scheme

1: 1.) NaNO2, 40percent H2SO4; 2.) CuSO4.5H2O, NaCl / 1.) water, -12 deg C, 2 h; 2.) water, -2 deg C, 2 h, room temperature 2: 98 percent / hydrogen chloride / ice-cooling 3: 99 percent / H2, triethylamine / 10percent Pd-C / ethanol 4: 78 percent / methanol 5: 88 percent / p-TsOH / toluene / 4 h / Heating View Scheme

1: 99 percent / H2, triethylamine / 10percent Pd-C / ethanol 2: 78 percent / methanol 3: 88 percent / p-TsOH / toluene / 4 h / Heating View Scheme

1: 98 percent / hydrogen chloride / ice-cooling 2: 99 percent / H2, triethylamine / 10percent Pd-C / ethanol 3: 78 percent / methanol 4: 88 percent / p-TsOH / toluene / 4 h / Heating View Scheme

1: 78 percent / methanol 2: 88 percent / p-TsOH / toluene / 4 h / Heating View Scheme