Dimethyl Sulfoxide → 1-Phenylpent-1-yn-3-one

Participants

Reaction Conditions

Reaction Steps

To a solution of oxalyl chloride (0.168 mL, 1.92 mmol) in dichloromethane (2.5 mL) at −78° C. was added dimethylsulfoxide (0.231 mL, 3.26 mmol) dropwise followed by 1-phenylpent-1-yn-3-ol (61.4 mg, 0.383 mmol) in 0.5 mL of dichloromethane dropwise. The reaction mixture was stirred at −78° C. for 1 h., and triethylamine (0.534 mL, 3.83 mmol) was then added dropwise. The reaction mixture was warmed to room temperature and stirred for 1 h. The reaction mixture was diluted with dichloromethane (2.5 mL), washed with water (1 mL), washed with a saturated aqueous solution of sodium bicarbonate (1 mL), washed with brine (1 mL), and dried over anhydrous sodium sulfate. Concentration followed by purification by silica gel chromatography with hexanes/ethyl acetate (10/1) afforded 1-phenylpent-1-yn-3-one (37 mg). The compound had an HPLC ret. time=2.88 min.−Column. YMC S5 COMBISCREEN® 4.6×50 mm; Gradient time: 4 min; Flow rate=4 ml/min; Solvent A=10% MeOH−90% Water−0.2% H3PO4; Solvent B=90% MeOH−10% water−0.2% H3PO4; Start % B=0; Final % B=100. LC-MS: M+1=159+.

Provenance & Evidence