1: 43 percent / DBU / tetrahydrofuran / 1 h / 0 °C 2: 70 percent / 2-acetylnaphthalene / methanol / Irradiation; 1.) 0 deg C, 2 h, 2.) r.t., 12 h 3: 61 percent / 2-acetylnaphthalene / diethyl ether / 5 h / Ambient temperature; Irradiation View Scheme