1: 74 percent / potassium t-butylate / dioxane / 1.) 30 min, room temperature, 2.) 2 h, reflux 2: 91 percent / conc. H2SO4 / H2O; acetic acid / 1.5 h / Heating View Scheme

potassium tert-butylate in 1,4-dioxane 1.) 30 min, room temperature, 2.) 2 h, reflux;