18-crown-6 ether; cesium fluoride in benzene (Ar); addn. of CsF to a mixt. of phenylacetylene and 18-crown-6 in C6H6,stirring for 5 min, addn. of germanium compd., stirring at room temp. f or 5-7 h; filtration through SiO2 or Al2O3, evapn.;

methylmagnesium bromide in diethyl ether (Ar); drop a soln. of MeMgBr to a soln. of educt at 0°C; stirring for 30 min at 0°C and then for 3 h at 20°C; evapn. of solvent (vac.); distn. (vac.);