A solution of dimethyl-1-diazo-2-oxopropylphosphonate and the aldehyde 12 in methanol is created and the potassium carbonate is added at 0°C under argon atmosphere. The mixture is stirred for 2.5 hours. Aqueous saturated ammonium chloride and pentane were then added. The organic layer was separated, dried with sodium sulfate, and evaporated. An 88% yield of acetylene 13 was collected using column chromatography on silica gel.