1: p-toluenesulfonic acid / propan-2-ol / 5 h / Ambient temperature 2: POCl3 / 0.17 h / 80 - 90 °C 3: 1.) CH3ONa / 1.) methanol, reflux, 1 h; 2.) methanol, reflux, 21.5 h. View Scheme

1: POCl3 / 0.17 h / 80 - 90 °C 2: 1.) CH3ONa / 1.) methanol, reflux, 1 h; 2.) methanol, reflux, 21.5 h. View Scheme

sodium methylate 1.) methanol, reflux, 1 h; 2.) methanol, reflux, 21.5 h.; Yield given. Multistep reaction;