1: 1) magnesium ethylate / 1.) toluene, 2 h, reflux, 2.) toluene, acetonitrile, 2 h, r.t. 2: 65 percent / conc. H2SO4 / 15 h / Ambient temperature View Scheme

1: 1.) magnesium ethoxide / 1.) toluene, reflux, 2 h, 2.) acetonitrile, room temp., 3 h 2: 68 percent / acetic acid / 1 h / Heating View Scheme

1: 1.) magnesium ethoxide / 1.) toluene, reflux, 2 h, 2.) acetonitrile, room temp., 2 h 2: 61 percent / polyphosphoric acid / 1 h / 120 °C View Scheme