1: 80 percent / tetramethylguanidine / 168 h / Ambient temperature 2: 70 percent / hydrogen / Raney-nickel / methanol / 150 °C / 76000.1 Torr 3: 75 percent / hydrogen, 2 N hydrochloric acid / 10percent Pd/C / ethanol; H2O / 40 °C View Scheme

sodium ethanolate in ethanol 3 h; Heating; Yield given;

1: 2.) hydrochloric acid / 1.) water, ethanol, reflux, 60 h; 2.) water, reflux, 30 h 2: 1.) sodium ethoxide / 1.) ethanol, 20 min; 2.) ethanol, dimethylformamide, 90 deg C, 3 h 3: 75 percent / hydrogen, 2N hydrocloric acid / 10percent Pd/C / ethanol; H2O / 40 °C View Scheme