1: 95 percent / Amberlite 120 ion exchange resin / methanol / 16 h / Ambient temperature 2: 86 percent / N-bromosuccinimide, PPh3 / CH2Cl2 / 1.) 10-18 deg C; 2.) 45 min, r.t. 3: 38 percent / ethylenediamine / dimethylsulfoxide / 1.) 8 deg C; 2.) 20 min, r.t. View Scheme

Multi-step reaction with 3 steps 1: 95 percent / Amberlite 120 ion exchange resin / methanol / 16 h / Ambient temperature2: 86 percent / N-bromosuccinimide, PPh3 / CH2Cl2 / 1.) 10-18 deg C; 2.) 45 min, r.t.3: 51 percent / ethylenediamine / dimethylsulfoxide / 1.) 8 deg C; 2.) 20 min, r.t.