1: 2'-bromo-2,6-bis(1-methylethoxy)biphenyl With n-butyllithium in tetrahydrofuran; hexane T=-78°C; 1 h; 2: chloro-dicyclohexylphosphine in tetrahydrofuran; hexane T=-78 - 20°C;

1.1: n-BuLi / hexane / 2.5 h / Heating 1.2: hexane / 1.83 h / Heating 2.1: n-BuLi / tetrahydrofuran; hexane / 1 h / -78 °C 2.2: 2.24 percent / tetrahydrofuran; hexane / -78 - 20 °C View Scheme

1.1: 95 percent / K2CO3 / dimethylformamide / 24 h / 70 °C 2.1: n-BuLi / hexane / 2.5 h / Heating 2.2: hexane / 1.83 h / Heating 3.1: n-BuLi / tetrahydrofuran; hexane / 1 h / -78 °C 3.2: 2.24 percent / tetrahydrofuran; hexane / -78 - 20 °C View Scheme

in further solvent(s) treatment of palladium compd. with chlorobenzene deriv. and phosphine deriv. in methyl tert-butyl ether at 55°C; recrystn.;