1: caesium carbonate / acetonitrile / 18 h / 20 - 60 °C 2: hydrogen; palladium on activated charcoal / methanol; ethyl acetate 3: potassium acetate; acetic anhydride / benzene 4: caesium carbonate / N,N-dimethyl-formamide 5: potassium hydroxide / tetrahydrofuran; water / 3 h View Scheme

1.1: tert-butyl methyl ether / 760.05 Torr / |Heating; |Inert atmosphere 1.2: 36 h / 65 °C / |Heating; |Inert atmosphere 2.1: potassium hydroxide / tetrahydrofuran; water / 3 h View Scheme