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

trifluoroacetic acid 10 h; Heating;

1: 51 percent / n-BuLi, N,N,N'-trimethylethylenediamine / tetrahydrofuran; hexane / 1.) -20 deg C, 15 min; -20 deg C, 3 h, 2.) r.t., overnight 2: aq. NaClO2, NaH2PO4*H2O, 2-methyl-2-butene / 2-methyl-propan-2-ol / 16 h / Ambient temperature 3: (COCl)2 / CH2Cl2 / 3 h / Ambient temperature 4: aq. NaN3 / benzene / 1.) 0 deg C, 15 min, 2.) r.t., 1 h 5: toluene / 1 h / Heating 6: 68 percent / Et3N, Cl3SiH / CH2Cl2 / 1.) 0 deg C, 1.5 h, 2.) r.t., 30 min 7: 53 percent / Me6Sn2 / benzene / 5 h / 70 °C / Irradiation 8: 76 percent / TFA / 10 h / Heating View Scheme

1: 78 percent / NaH, LiBr / 1,2-dimethoxy-ethane; dimethylformamide / 1.) 0 deg C, 10 min; r.t., 15 min, 2.) toluene, 70 deg C, 20 h 2: 53 percent / Me6Sn2 / benzene / 5 h / 70 °C / Irradiation 3: 76 percent / TFA / 10 h / Heating View Scheme

1: 53 percent / Me6Sn2 / benzene / 5 h / 70 °C / Irradiation 2: 76 percent / TFA / 10 h / Heating View Scheme

1: 73 percent / Me3SiCl, NaI / acetonitrile; H2O / 5 h / 65 °C 2: 78 percent / NaH, LiBr / 1,2-dimethoxy-ethane; dimethylformamide / 1.) 0 deg C, 10 min; r.t., 15 min, 2.) toluene, 70 deg C, 20 h 3: 53 percent / Me6Sn2 / benzene / 5 h / 70 °C / Irradiation 4: 76 percent / TFA / 10 h / Heating View Scheme

1: aq. NaClO2, NaH2PO4*H2O, 2-methyl-2-butene / 2-methyl-propan-2-ol / 16 h / Ambient temperature 2: (COCl)2 / CH2Cl2 / 3 h / Ambient temperature 3: aq. NaN3 / benzene / 1.) 0 deg C, 15 min, 2.) r.t., 1 h 4: toluene / 1 h / Heating 5: 68 percent / Et3N, Cl3SiH / CH2Cl2 / 1.) 0 deg C, 1.5 h, 2.) r.t., 30 min 6: 53 percent / Me6Sn2 / benzene / 5 h / 70 °C / Irradiation 7: 76 percent / TFA / 10 h / Heating View Scheme

1: 45 percent / ICl / CCl4; CH2Cl2 / 48 h / Ambient temperature 2: 73 percent / Me3SiCl, NaI / acetonitrile; H2O / 5 h / 65 °C 3: 78 percent / NaH, LiBr / 1,2-dimethoxy-ethane; dimethylformamide / 1.) 0 deg C, 10 min; r.t., 15 min, 2.) toluene, 70 deg C, 20 h 4: 53 percent / Me6Sn2 / benzene / 5 h / 70 °C / Irradiation 5: 76 percent / TFA / 10 h / Heating View Scheme