caesium carbonate in methanol; hexane; water; butanone

in dichloromethane; ethyl acetate

1: iodine cloride; acetic acid; sodium acetate / dichloromethane / 0.5 h / 90 °C 2: triethylamine; 4-(N,N-dimethlyamino)pyridine / dichloromethane / 18 h / 20 °C 3: trifluoroacetic acid / dichloromethane / 3 h / 0 - 20 °C View Scheme

1: triethylamine; 4-(N,N-dimethlyamino)pyridine / dichloromethane / 18 h / 20 °C 2: trifluoroacetic acid / dichloromethane / 3 h / 0 - 20 °C View Scheme