1: 61 percent / hexamethylenetetramine, glacial acetic acid, sulfuric acid / 18 h / 25 °C 2: 80 percent / potassium carbonate, N, N-dimethylformamide / 1.5 h / Heating 3: 49 percent / trifluoroacetic acid / 0.25 h / Heating 4: 1) sodium methylsulfinylmethide / 1) dimethyl sulfoxide, tetrahydrofuran, 0 deg C, 2 min, 2) tetrahydrofuran, 0 deg C, 30 min, then 24 deg C, 1 h 5: hexane; methanol / 14 h / Heating View Scheme

1: 1) potassium tert-butoxide / 1) tert-butyl alcohol, reflux, o.5 h, 2) tert-butyl alcohol, reflux, 8 h 2: 82 percent / N,N-dimethylaniline / 2.5 h / 193 °C 3: 84 percent / m-chloroperbenzoic acid / CH2Cl2 / 0 deg C to 22 deg C, 22 h 4: 75 percent / potassium hydroxide, water / dimethylsulfoxide / 3 h / 23 °C 5: 82 percent / triethylamine, 4-dimethyl-aminopyridine / CH2Cl2 / 10 h / Ambient temperature 6: 95 percent / benzoyl peroxiden, N-bromosuccinimide / CCl4 / Heating; Irradiation 7: 61 percent / mercuric acetate / 2 h / Heating 8: 86 percent / ammonia, methanol / 10 h / Ambient temperature 9: 78 percent / 2 M oxalyl chloride, dimethyl sulfoxide, triethylamine / CH2Cl2 / -60 °C 10: 97 percent / p-toluenesulfonic acid / benzene / 4 h / Heating 11: 91 percent / sodium hydroxide, water / tetrahydrofuran / 4 h / 24 °C 12: 70 percent / pyridine, chromium trioxide / CH2Cl2 / 0.5 h / 23 °C 13: 1) sodium methylsulfinylmethide / 1) dimethyl sulfoxide, tetrahydrofuran, 0 deg C, 2 min, 2) tetrahydrofuran, 0 deg C, 30 min, then 25 deg C, 1 h 14: 51 percent / benzene; methanol / 16 h / Heating 15: 84 percent / hydrogen, triethylamine / 5 percent palladium on carbon / ethanol / 775.7 Torr View Scheme

1: 61 percent / hexamethylenetetramine, glacial acetic acid, sulfuric acid / 18 h / 25 °C 2: 80 percent / potassium carbonate, N, N-dimethylformamide / 1.5 h / Heating 3: 49 percent / trifluoroacetic acid / 0.25 h / Heating 4: 1) sodium methylsulfinylmethide / 1) dimethyl sulfoxide, tetrahydrofuran, 0 deg C, 2 min, 2) tetrahydrofuran, 0 deg C, 30 min, then 24 deg C, 1 h 5: hexane; methanol / 14 h / Heating 6: hydrochloric acid / ethanol 7: 93 percent / hydrogen / 5 percent palladium on carbon / ethanol / 0.25 h / 775.7 Torr View Scheme

1: 61.1 percent / sulfuric acid / benzene / 7.5 h / 65 °C 2: 57.8 percent / 10 percent NaOH / Raney nickel-aluminum alloy / ethanol; H2O / 1.) r.t., 3.5 h; 2.) reflux, 2 h View Scheme