triethylaluminum; bis(acetylacetonate)nickel(II); triphenylphosphine in toluene T=60 - 80°C; 5 h;

triethylaluminum; pyridine; bis(acetylacetonate)nickel(II) in tetrahydrofuran; toluene T=80 - 100°C; 5 h;

Multi-step reaction with 4 steps 1: 92 percent / benzene / 1 h / 25 °C2: 98 percent / ethyl chloroformate, triethylamine / tetrahydrofuran / 1 h / -12 °C3: 97 percent / tetrahydrofuran / 1 h / -12 °C4: 1.) NaH / 1.) THF, mineral oil, 2.) THF, r.t., 12 h