1: sodium methylate / methanol; N,N-dimethyl-formamide / 12 h / 120 °C / |Inert atmosphere 2: toluene-4-sulfonic acid / tetrahydrofuran / 0.25 h / |Inert atmosphere; |Reflux 3: triethylamine / dichloromethane / 2 h / 20 °C / |Inert atmosphere 4: palladium diacetate; triphenylphosphine; potassium carbonate / N,N-dimethyl-formamide / 120 °C / |Reflux; |Inert atmosphere 5: ammonium cerium (IV) nitrate / acetonitrile; water / 0.25 h / |Inert atmosphere 6: palladium(II) oxide hydrate; hydrogen / methanol / 3 h / |Inert atmosphere View Scheme

1: sodium methylate / methanol; N,N-dimethyl-formamide / 12 h / 120 °C / |Inert atmosphere 2: toluene-4-sulfonic acid / tetrahydrofuran / 0.25 h / |Inert atmosphere; |Reflux 3: triethylamine / dichloromethane / 2 h / 20 °C / |Inert atmosphere 4: palladium diacetate; triphenylphosphine; potassium carbonate / N,N-dimethyl-formamide / 120 °C / |Reflux; |Inert atmosphere 5: ammonium cerium (IV) nitrate / acetonitrile; water / 0.25 h / |Inert atmosphere View Scheme