1: With sodium hydroxide in water T=20°C; 0.5 h; 2: With hydrogenchloride in water T=20°C; 1 h;

1.1: N,N,N',N,-tetramethylethylenediamine / tetrahydrofuran / 50 °C / |Inert atmosphere 2.1: sodium hydroxide / water / 0.5 h / 20 °C 2.2: 1 h / 20 °C View Scheme