1: 89 percent / dimethylformamide / 6 h / Ambient temperature 2: 1.) NaHPO4, 6percent natrium amalgame, 2.) p-toluenesulfonic acid / 1.) methanol, 2.) ethanol, water, 16 h, reflux View Scheme

disodium hydrogenphosphate; sodium amalgam; toluene-4-sulfonic acid 1.) methanol, room temp., 30 min, 2.) ethanol, reflux, 20 h; Yield given. Multistep reaction. Yields of byproduct given;