CuCN*2LiCl in tetrahydrofuran T=-78°C; 1 h;

Multi-step reaction with 2 steps 1: 100 percent / chlorobenzene / 48 h / Heating2: 1.) PhLi, 3.) PhLi / 1.) THF, room t., 10 min, 2.) THF, ether. -78 deg C, then -70- -40 deg C, 5 min, 3.) THF, ether -30 deg C, 5 min