1: With lithium hexamethyldisilazane in toluene T=0 - 25°C; Claisen condensation; 2 h; 2: With sodium hydroxide in ethanol; water T=0 - 80°C; Claisen condensation; 1.5 h; 3: With hydrogenchloride in water T=25 - 60°C; Claisen condensation; 2.5 h;

hydrogenchloride in methanol 1 h; Heating;

1.1: potassium carbonate; potassium iodide / acetone / 5 h / 50 °C 2.1: lithium hexamethyldisilazane / toluene / 2 h / 0 - 25 °C 2.2: 1.5 h / 0 - 80 °C 2.3: 2.5 h / 25 - 60 °C View Scheme