1: 2-ethynyl-2-phenyl-[1,3]dithiolane With methyl-magnesium iodide in diethyl ether T=20°C; 0.5 h; 2: 1-(iodo)-4-methylbenzene With triphenylphosphine; tris(dibenzylideneacetone)dipalladium (0) in tetrahydrofuran; diethyl ether Kumada-Corriu cross-coupling; Heating; Further stages.;