hydrogenchloride T=80°C; 24 h; in sealed tube;

1: pyridine 2: TMS-OTf View Scheme

1: 42 h / Ambient temperature 2: HCl(g) / acetonitrile / 20 h / -42 - 20 °C 3: 1,8-diazabicyclo<5.4.0>undec-7-ene / benzene / Ambient temperature View Scheme

boron trifluoride diethyl etherate

perchloric acid T=40°C; 2.5 h;

T=0 - 20°C; 16 h; Inert atmosphere;

1: 42 h / Ambient temperature 2: HCl(g) / acetonitrile / 20 h / -42 - 20 °C 3: 1,8-diazabicyclo<5.4.0>undec-7-ene / benzene / Ambient temperature 4: BF3*Et2O / benzene; methanol / 18 h / Ambient temperature 5: 50percent aq. AcOH / ethyl acetate / Ambient temperature 6: 87 percent / diphenylphosphoryl azide, 1,8-diazabicyclo<5.4.0>undec-7-ene / 23 h / Ambient temperature 7: 78 percent / H2S, pyridine / 1.5 h / Ambient temperature 8: diisopropylethylamine / dimethylformamide / 96 h / Ambient temperature 9: aq. NaOH / methanol / Ambient temperature View Scheme

1: 42 h / Ambient temperature 2: HCl(g) / acetonitrile / 20 h / -42 - 20 °C 3: 1,8-diazabicyclo<5.4.0>undec-7-ene / benzene / Ambient temperature 4: BF3*Et2O / benzene; methanol / 18 h / Ambient temperature 5: 50percent aq. AcOH / ethyl acetate / Ambient temperature 6: 87 percent / diphenylphosphoryl azide, 1,8-diazabicyclo<5.4.0>undec-7-ene / 23 h / Ambient temperature View Scheme

1.1: pyridine / 20 °C / Cooling with ice 2.1: trimethylsilyl trifluoromethanesulfonate / ethyl acetate / 3 h / 30 - 52 °C / Inert atmosphere 3.1: trimethylsilylazide / tert-butyl alcohol / Inert atmosphere; Reflux 3.2: 1 h 4.1: hydrogen; acetic acid / palladium 10 on activated carbon / toluene; methanol / 1 h View Scheme

sulfuric acid in n-heptane T=0 - 40°C; 4 h; Product distribution / selectivity;