1.1: acetic acid / acetic acid / 88 °C 2.1: thionyl chloride / N,N-dimethyl-formamide / 0.75 h / Reflux 2.2: 20 - 60 °C 3.1: ammonium formate / palladium on activated charcoal / ethanol / 3 h / Reflux 4.1: 1,1'-carbonyldiimidazole / tetrahydrofuran / 1 h / Reflux 4.2: 10 h / Reflux 5.1: hydrogenchloride; toluene-4-sulfonic acid / ethanol / 48 h / 20 °C 5.2: 10 - 20 °C 5.3: 0.75 h / 50 °C 6.1: potassium carbonate / water; acetone / 0.5 h / 5 °C 6.2: 1 h / 50 °C 6.3: 1 h / Reflux View Scheme

1.1: sodium hydroxide / acetone / 0.25 h / 5 - 20 °C 2.1: sodium hydroxide / water; acetic acid n-butyl ester / 50 °C 2.2: 2 h / 40 °C 3.1: acetone / 6 h / 0 - 33 °C / Reflux View Scheme

1.1: dichloromethane / 2.5 h / 25 - 35 °C 2.1: potassium carbonate / acetonitrile; water / 0.25 h / 12 - 18 °C 2.2: 14.42 h / 12 - 20 °C 3.1: ethyl acetate; ethanol / 8 h / 25 - 35 °C View Scheme

1.1: hydrogenchloride; toluene-4-sulfonic acid / ethanol / 48 h / 20 °C 1.2: 10 - 20 °C 1.3: 0.75 h / 50 °C 2.1: potassium carbonate / water; acetone / 0.5 h / 5 °C 2.2: 1 h / 50 °C 2.3: 1 h / Reflux View Scheme

1.1: sodium hydroxide / acetone / 0.25 h / 5 - 20 °C 2.1: sodium hydroxide / water; acetic acid n-butyl ester / 50 °C 2.2: 2 h / 40 °C 3.1: acetone / 6 h / 0 - 33 °C / Reflux View Scheme

1: potassium carbonate / water; acetone / 15 °C 2: ethyl acetate; ethanol / 8 h / 25 - 35 °C View Scheme

1.1: triethylamine / tetrahydrofuran; dichloromethane / 2 h / 40 °C 2.1: palladium on activated charcoal; hydrogen / water; ethanol / 50 °C / |Autoclave 3.1: 1,1'-carbonyldiimidazole / tetrahydrofuran / 0.67 h / |Inert atmosphere; |Reflux 3.2: 7 h / |Inert atmosphere; |Reflux 3.3: 3 h / |Reflux 4.1: hydrogenchloride / ethanol; dichloromethane / 6 h / 15 - 30 °C 4.2: 15 - 30 °C 5.1: triethylamine / water; acetonitrile / 15 °C 6.1: acetone / |Heating View Scheme

1.1: palladium on activated charcoal / ethyl acetate / 0.33 h / 25 - 55 °C / |High pressure 2.1: 1,1'-carbonyldiimidazole / toluene / 2 h / 55 - 60 °C 2.2: 6 h / 60 - 100 °C 3.1: hydrogenchloride / ethanol / 25 - 35 °C 4.1: potassium carbonate / water; acetone / 1 h / 10 °C 5.1: acetone / 2 h / 25 - 30 °C View Scheme

1.1: hydrogenchloride / ethanol / 5 - 30 °C 1.2: 3 h / 25 - 30 °C 2.1: acetone / 2 h / 17 - 36 °C View Scheme

1.1: potassium carbonate / water; tetrahydrofuran 1.2: 2 h / 25 - 30 °C 2.1: acetone / 2 h / 17 - 36 °C View Scheme