1: trimethylaluminum; 6,10,14-Trimethyl-pentadec-1-yne With zirconocene dichloride in 1,2-dichloro-ethane 2: With n-butyllithium in tetrahydrofuran 3: formaldehyd in tetrahydrofuran Further stages.;

n-butyllithium; zirconocene dichloride; triphenylphosphine; nickel dichloride 1.) ClCH2CH2Cl, 0 deg C, 2.) THF, -78 deg C to 0 deg C, 15 min; Yield given. Multistep reaction;