Acetic Acid → HCID 86740796, compound

Participants

Reaction Conditions

Reaction Steps

In a separate flask, the mesylate of 6-[(tetrahydro-2H-pyran-2-yl)oxy]-4-hexen-1-yn-3-ol was prepared via the following procedure. To a stirred solution of 6-(tetrahydro-2H-pyran-2-yl)oxy]-4-hexen-1-yn-3-ol (98 mg, 0.5 mmole), anhydrous lithium bromide (43 mg, 0.5 mmole) and a few milligrams of 1,10-phenanthroline in 5 ml of tetrahydrofuran at -78° C. was added n-butyllithium dropwise until a brown color was obtained (ca. 0.5 mmole of n-butyllithium). The mixture was stirred for one-half hour whereupon mesyl chloride (38 μl, 0.5 mmole) was added dropwise. The brown color discharged to yellow. The solution was stirred for 10 minutes at -78° C. and was then added all at once (via short teflon cannula and argon pressure) to the above stirred -20° C. solution of zinc diacetylene. The resultant mixture was stirred at -20° C. for 15 minutes and was then acidified by the addition of a solution of acetic acid in tetrahydrofuran. The mixture was then concentrated to ca. 1/4 volume and 30 ml of a mixture of ether-hexane 1:1 was added with stirring whereupon a gum separated. The supernatant was then filtered through a pad of silica gel. The filtrate was concentrated to dryness and immediately redissolved in a few ml of ether-hexane 1:5 (some solid did not dissolve). This solution of crude product was then purified via flash chromatography (LPS-1 silica gel, ether-hexane 1:10) to afford pure title compound (30 mg). This allene was stored in solution in ether-hexane in the freezer.

Provenance & Evidence