1: 1.) t-BuLi, TMEDA / 1.) pentane, room temp., 1 h, 2.) room temp., overnight 2: conc. HCl / pentane; methanol / 1.67 h / 0 °C View Scheme

1: sec.-butyllithium / tetrahydrofuran; cyclohexane / -78 - -50 °C 2: lithium triethylborohydride; Cl2Ni(1,2-bis(diphenylphosphino)ethane) / tetrahydrofuran / 3 h / 30 °C / |Inert atmosphere View Scheme

n-butyllithium 1.) THF, hexane, -78 deg C, 10 min, 2.) THF, hexane, from -78 deg C to RT; Yield given. Multistep reaction. Yields of byproduct given;