1: triethylamine / CCl4 2: 1.) 1,3-dibromo-5,5-dimethylhydantoin; 2.) 1,5-diazabicyclo<4.3.0>non-5-ene / 1.) tetrachloromethane, reflux 3: NH3 / ethanol / 2 h / Heating 4: KF / acetonitrile; H2O / 2.5 h / Heating View Scheme