hydrogen; Pd-Pb-CaCO3 (Lindlar catalyst) in hexane

[2,2']bipyridinyl; copper(l) iodide in tetrahydrofuran 1) 2 deg C, 2 h, 2) room temperature, 12 h;

1: 82 percent / Br2, triphenylphosphine, (C2H5)3N / CCl4 / 12 h / 20 °C 2: 74 percent / CuI, bi-2-pyridyl / tetrahydrofuran / 1) 2 deg C, 2 h, 2) room temperature, 12 h View Scheme

1: 64 percent / Fe acetylacetonate / bis-(2-methoxy-ethyl) ether; diethyl ether; liquid ammonia / from -30 to 30 deg C, 5 h, 30 deg C, 15 h 2: 82 percent / Br2, triphenylphosphine, (C2H5)3N / CCl4 / 12 h / 20 °C 3: 74 percent / CuI, bi-2-pyridyl / tetrahydrofuran / 1) 2 deg C, 2 h, 2) room temperature, 12 h View Scheme

n-butyllithium 1) THF, HMPA, 2) THF, HMPA; Yield given. Multistep reaction;

Yield given. Multistep reaction;

Yield given. Multistep reaction;

(i) Li, liq. NH3, (ii) /BRN= 1697464/; Multistep reaction;