thionyl chloride 3 h; Reflux;

sulfuric acid in methanol

hydrogenchloride in methanol; water Reflux;

in methanol; diethyl ether; toluene 2 h; Inert atmosphereSchlenk technique;

1: With chloroformic acid ethyl ester; triethylamine in tetrahydrofuran 0.25 h; Cooling with ice; 2: With sodium tetrahydroborate; water in tetrahydrofuran Cooling with ice;

1: thionyl chloride / 3 h / Reflux 2: N-bromosuccinmide; dibenzoyl peroxide / tetrachloromethane / 5 h / 80 - 85 °C View Scheme

1: thionyl chloride / 3 h / Reflux 2: N-bromosuccinmide; dibenzoyl peroxide / tetrachloromethane / 5 h / 80 - 85 °C 3: water; calcium carbonate / tetrahydrofuran / 5 h / 100 °C 4: silica gel; pyridinium chlorochromate / dichloromethane / 3 h / 0 - 10 °C View Scheme

1.1: thionyl chloride / 2 h / Reflux 2.1: triethylamine; magnesium chloride / acetonitrile / 2.5 h / 0 - 20 °C / Inert atmosphere 2.2: 20 °C 2.3: 3 h / Reflux View Scheme

1: triethylamine / dichloromethane / 0.17 h / 0 °C 2: ammonium hydroxide / 0.03 h / 0 °C 3: 2,4,6-trichloro-1,3,5-triazine / N,N-dimethyl-formamide / 0 - 20 °C 4: N-bromosuccinmide; dibenzoyl peroxide / tetrachloromethane / 16 h / Reflux; Inert atmosphere 5: N,N-dimethyl-formamide / 1 h / 80 °C 6: lithium hydroxide hydrate / tetrahydrofuran; methanol; water / 1 h / 20 °C 7: silica gel; pyridinium chlorochromate / dichloromethane / 2 h / 20 °C View Scheme

potassium carbonate; copper(I) oxide; copper in 2-ethoxy-ethanol T=130°C; 24 h;