Diethyl Ether → 1-(prop-2-ynyl)cyclopentanol

Participants

Reaction Steps

Magnesium turnings (350 mg, 14.4 mmol) and HgCl2 (16 mg, 0.659 mmol) were stirred with 20 mL of anhydrous diethyl ether in a 100-mL round bottom flask. Propargyl bromide (80% in xylene, 2.5 mL, 13.2 mmol) was added. The mixture was stirred for 30 min at room temperature before cyclopentanone (1.0 g, 11.9 mmol) was added in 4.0 mL tetrahydrofuran. The resulting mixture was refluxed for 2 h, then allowed to cool to room temperature, and quenched with saturated aqueous ammonium chloride (15 mL). The biphasic mixture was extracted with ethyl (50 mL) and the organic layer was washed with brine, dried over Na2SO4, filtered, and concentrated in vacuuo. The residue was purified by flash chromatograph on silica gel (eluting with 10% hexanes in ethyl acetate) to provide the title compound (800 mg, 54%) as a colorless oil.

Provenance & Evidence