1: trimethylsilylacetylene With n-butyllithium in tetrahydrofuran; hexane T=-78°C; Inert atmosphere; 2: isobutyraldehyde in tetrahydrofuran; hexane T=-78 - 20°C; 3: With water in tetrahydrofuran; hexane

1: (RS)-4-methyl-1-pentyn-3-ol With n-butyllithium in tetrahydrofuran; hexane T=-78 - 22°C; 2: chloro-trimethyl-silane in tetrahydrofuran; hexane T=-78 - 22°C; Further stages.;

in diethyl ether T=-30 - 20°C;

(i) AlCl3, (ii) aq. MeOH; Multistep reaction;