1.1: 1H-imidazole / N,N-dimethyl-formamide / 1.5 h / 0 - 20 °C / Inert atmosphere 2.1: sodium hydride / N,N-dimethyl-formamide; mineral oil / 0.5 h / 0 °C / Inert atmosphere 2.2: 13.5 h / 0 - 60 °C / Inert atmosphere 3.1: water; sodium hydroxide / tetrahydrofuran / 0.75 h / 20 °C 4.1: caesium carbonate / methanol / pH 7 4.2: 11 h / 0 - 20 °C / Inert atmosphere 5.1: pyridinium poly(hydrogen fluoride) / tetrahydrofuran / 12 h / 0 - 20 °C 6.1: toluene / 5 h / 60 °C / Inert atmosphere 7.1: 10 Pd(OH)2 on C; hydrogen / methanol / 36 h / 20 °C 8.1: piperidine; 4-(N,N-dimethlyamino)pyridine / N,N-dimethyl-formamide / 192 h / 20 °C / Inert atmosphere View Scheme

pyridine T=20°C; 2 h;

 Yield given. Multistep reaction;