1: 71 percent / triethylamine / acetonitrile / 2 h / 25 °C / edducts were added at 0 deg C 2: 1.) sodium ethoxide / 1.) ethanol, reflux, 0.25 h, 2.) 2 h View Scheme

sodium ethanolate 1.) ethanol, reflux, 0.25 h, 2.) 2 h; Yield given. Multistep reaction;