1: 55 percent / DIBAL-H / toluene / 3 h / 45 °C 2: 80 percent / PBr3 / diethyl ether / 1.5 h / 0 °C View Scheme

copper(l) iodide; n-butyllithium Yield given. Multistep reaction. Yields of byproduct given;

triethylsilane; palladium on activated charcoal in methanol 0.166667 h;

1: diisobutylaluminium hydride / dichloromethane / 4 h / -78 °C / |Inert atmosphere 2: N-bromosuccinmide; dimethylsulfide / dichloromethane / 0.17 h / |Inert atmosphere 3: cupric bromide-dimethyl sulfide; (R)-(S)-PPF-PCy2 / dichloromethane / 1 h / |Inert atmosphere View Scheme