1: anhydrous 1-octyne With Schwartz's reagent in tetrahydrofuran T=20°C; 1 h; 2: trans-2-phenylsulphonyl-3-propyloxirane With lithium diisopropyl amide in tetrahydrofuran; n-heptane; ethylbenzene T=-90 - -60°C; 1 h; 3: butyraldehyde With boron trifluoride diethyl etherate in tetrahydrofuran; n-heptane; ethylbenzene T=-60 - 20°C; 3 h;