1: 85 percent / K2CO3 / acetonitrile / 4 h / Heating 2: 77 percent / 30percent ethanolic HCl / ethyl acetate / 1 h / Ambient temperature 3: 1.) FeCl3*6H2O, activated carbon, 2.) hydrazine monohydrate / 1.) MeOH, THF, reflux, 30 min, 2.) MeOH, THF, reflux, 14 h 4: 91 percent / acetic acid / 0.67 h / 80 - 90 °C 5: 100 percent / trimethyltin azide / toluene / 29 h / Heating 6: 85 percent / 1 N aq. NaOH / methanol / 1 h / 80 - 90 °C View Scheme

1: With tetrabutylammomium bromide; potassium carbonate in toluene T=80 - 85°C; 12 h; 2: With hydrogenchloride in methanol; water 3 h; Reflux;

1: 85 percent / K2CO3 / acetonitrile / 4 h / Heating 2: 77 percent / 30percent ethanolic HCl / ethyl acetate / 1 h / Ambient temperature View Scheme

1.1: potassium carbonate; tetrabutylammomium bromide / toluene / 12 h / 80 - 85 °C 1.2: 3 h / Reflux 2.1: tin(ll) chloride / ethyl acetate / 1.5 h / Reflux 2.2: 4.5 h / -10 - 0 °C 2.3: 0.5 h / Reflux 3.1: acetic acid / toluene / 6 h / Reflux 4.1: sodium azide; tributyltin chloride / toluene / 100 h / Reflux 4.2: 0 - 20 °C 5.1: sodium hydroxide; water / ethanol / 3.5 h / Reflux 5.2: 3 h / 0 °C / pH 4 6.1: triethylamine / dichloromethane / 8 h / 0 - 20 °C View Scheme

1.1: potassium carbonate; tetrabutylammomium bromide / toluene / 12 h / 80 - 85 °C 1.2: 3 h / Reflux 2.1: tin(ll) chloride / ethyl acetate / 1.5 h / Reflux 2.2: 4.5 h / -10 - 0 °C 2.3: 0.5 h / Reflux 3.1: acetic acid / toluene / 6 h / Reflux 4.1: sodium azide; tributyltin chloride / toluene / 100 h / Reflux 4.2: 0 - 20 °C 5.1: sodium hydroxide; water / ethanol / 3.5 h / Reflux 5.2: 3 h / 0 °C / pH 4 6.1: triethylamine / dichloromethane / 8 h / 0 - 20 °C 7.1: potassium carbonate; potassium iodide / N,N-dimethyl-formamide / 2 h / 75 °C 8.1: hydrogen / palladium 10 on activated carbon / toluene; methanol / 20 °C / 2280.15 Torr View Scheme

1: 85 percent / K2CO3 / acetonitrile / 4 h / Heating 2: 77 percent / 30percent ethanolic HCl / ethyl acetate / 1 h / Ambient temperature 3: 1.) FeCl3*6H2O, activated carbon, 2.) hydrazine monohydrate / 1.) MeOH, THF, reflux, 30 min, 2.) MeOH, THF, reflux, 14 h 4: 91 percent / acetic acid / 0.67 h / 80 - 90 °C View Scheme

1: 85 percent / K2CO3 / acetonitrile / 4 h / Heating 2: 77 percent / 30percent ethanolic HCl / ethyl acetate / 1 h / Ambient temperature 3: 1.) FeCl3*6H2O, activated carbon, 2.) hydrazine monohydrate / 1.) MeOH, THF, reflux, 30 min, 2.) MeOH, THF, reflux, 14 h 4: 91 percent / acetic acid / 0.67 h / 80 - 90 °C 5: 100 percent / trimethyltin azide / toluene / 29 h / Heating View Scheme

1: 85 percent / K2CO3 / acetonitrile / 4 h / Heating 2: 77 percent / 30percent ethanolic HCl / ethyl acetate / 1 h / Ambient temperature 3: 1.) FeCl3*6H2O, activated carbon, 2.) hydrazine monohydrate / 1.) MeOH, THF, reflux, 30 min, 2.) MeOH, THF, reflux, 14 h View Scheme

hydrogen; palladium on activated charcoal in methanol T=20°C; 5 h;