1: 1.) sodium hydride / 1.) rt, 30 min, DMF; 2.) 120 deg C, 6 days 2: aq. HCl; dioxane / 1.5 h / Ambient temperature 3: 42 percent / para-toluenesulfonic acid / toluene / 0.33 h / Heating View Scheme

Multistep reaction;