Ethynyl(phenyl)iodonium Tetrafluoroborate [Ethynylating Reagent]

Typical Procedure:
A solution of 1,3-dicarbonyl compound (76 mg, 0.40 mmol) and NaH (11 mg, 0.48 mmol) in THF (2 mL) is stirred at rt for 1 h under an atmosphere of nitrogen. Ethynyl(phenyl)iodonium tetrafluoroborate¹⁾ (150 mg, 0.48 mmol) is then added and the resulting mixture is stirred at rt for 3 h. The reaction mixture is diluted with H₂O (5 mL) and extracted with Et₂O (3 x 10 mL). The combined organic layers are dried over MgSO₄ and the solvent is removed under reduced pressure. The crude product is purified by silica gel flash chromatography (Hexane : EtOAc = 20 : 1) to afford the ethynylated compound (59 mg, 69%) as yellow solid.