1: 1.) pyridine, 2.) aq. NaOH / 1) room temperature, 16 h; 2) methanol, reflux, 1 h 2: 26 percent / trimethylsilyl polyphosphate / dimethylformamide / 4 h / 130 °C 3: 77 percent / aq. HCl / ethanol / 2 h / Heating 4: dimethylformamide / 3 h / 75 °C View Scheme

pyridine; sodium hydroxide 1) room temperature, 16 h; 2) methanol, reflux, 1 h; Yield given. Multistep reaction;

1: 1.) pyridine, 2.) aq. NaOH / 1) room temperature, 16 h; 2) methanol, reflux, 1 h 2: 26 percent / trimethylsilyl polyphosphate / dimethylformamide / 4 h / 130 °C 3: 77 percent / aq. HCl / ethanol / 2 h / Heating View Scheme