polyphosphoric acid trimethylsilyl ester in 1,2-dichloro-ethane T=83°C; 0.5 h;

palladium diacetate; 1,3-bis-(diphenylphosphino)propane in toluene T=140°C; P=51680 Torr; 44 h; Yield given. Yields of byproduct given. Title compound not separated from byproducts;

palladium diacetate; 1,3-bis-(diphenylphosphino)propane in toluene T=140°C; P=51680 Torr; 44 h; Yield given. Yields of byproduct given. Title compound not separated from byproducts;

1: 81 percent / EtMgBr / diethyl ether / 1.) reflux, 30 min, 2.) 0 deg C, 10 min 2: 54 percent / polyphosphoric acid trimethylsilyl ester / 1,2-dichloro-ethane / 0.5 h / 83 °C View Scheme