1: potassium carbonate / methanol / 3 h / 20 °C / Inert atmosphere 2: potassium carbonate / acetone / 9.5 h / 20 °C / Inert atmosphere 3: AlCl3, aluminium chloride / dichloromethane / 0 - 20 °C 4: lithium hexamethyldisilazane / tetrahydrofuran / -30 - 0 °C / Inert atmosphere 5: trifluoroacetic acid / methanol / 24 h / 50 °C View Scheme

1: potassium carbonate / methanol / 3 h / 20 °C / Inert atmosphere 2: potassium carbonate / acetone / 9.5 h / 20 °C / Inert atmosphere 3: AlCl3, aluminium chloride / dichloromethane / 0 - 20 °C 4: lithium hexamethyldisilazane / tetrahydrofuran / -30 - 0 °C / Inert atmosphere 5: trifluoroacetic acid / methanol / 24 h / 50 °C 6: AlCl3, aluminium chloride; ethanethiol / CHCl2 / 0 - 20 °C View Scheme