1: pyridinium p-toluenesulfonate / dichloromethane / 8 h / Ambient temperature 2: hydrogen / palladium on carbon / ethanol 3: pyridine / 48 h / Ambient temperature 4: N,N,N',N',N'',N''-hexamethylphosphoric triamide; sodium hydride / 1.) DMF, RT, 24 h, 2.) DMF, 50 deg C, 7 d 5: hydrogenchloride / methanol / 12 h / Ambient temperature View Scheme