in pyridine T=0°C; 0.333333 h;

tetrakis(triphenylphosphine) palladium(0); caesium carbonate in N,N-dimethyl-formamide T=130°C; Inert atmosphereSealed tube;

1: 1.) t-BuLi, ZnCl2, 2.) LiCl, Pd(PPh3)4 / 1.) THF, pentane, -78 deg C, 30 min, 25 deg C, 2 h, 2.) reflux, 15 h 2: 99 percent / LDA / tetrahydrofuran / 1 h / -78 °C 3: 98 percent / CsF / dimethylformamide / 3 h / 25 °C View Scheme

tetrakis(triphenylphosphine) palladium(0); tert.-butyl lithium; lithium chloride; zinc(II) chloride 1.) THF, pentane, -78 deg C, 30 min, 25 deg C, 2 h, 2.) reflux, 15 h; Yield givenMultistep reaction;