1: α,α-diisopropyl-β-methylhomoallylic alcohol With methyl-magnesium iodide in 1,4-dioxane T=25°C; 1 h; 2: 1-Dodecyne With gallium(III) chloride in 1,4-dioxane; hexane 2 h; Heating; Further stages.;

lithium tetrachloromanganate(II) T=25°C; 3 h;