triethylamine in dichloromethane 24 h;

1: CH2Cl2; diethyl ether / 24 h / Ambient temperature 2: 1.) Br2, 2.) conc. HCl / 1.) CH2Cl2,, RT, 30 min, 2.) reflux, 1 d 3: 41 percent / CH2Cl2; diethyl ether / 0.17 h / Ambient temperature View Scheme

in diethyl ether; dichloromethane 0.166667 h; Ambient temperature;