Hydrofluoric Acid → (S)-2-methyl-4-methylidene-3-(2-propynyl)cyclopent-2-ene-1-ol

Participants

Reaction Steps

3 To a solution of (S)-2-methyl-4-methylidene-3-(2-propynyl)-1-tert-butyldimethylsilyl-oxycyclopent-2-ene (7.52 g, obtained above) in tetrahydrofuran (50 ml) was added a solution mixture (30 ml) consisting of tetrahydrofurane solution (80 parts) of 1M tetrabutylammonium fluoride and 46% hydrogenfluoride (3 parts) under ice-water cooling. The solution was then stirred at room temperature for 14 hours. The reaction solution was poured into ice-water, and then extracted with ether (150 ml ×2). The ether layers were combined, and washed with brine, and dried over anhydrous sodium sulfate. The solvent was evaporated under reduced pressure. The resultant residue was subjected to silica gel column chromatography (eluent; n-hexane: ethyl acetate=2:1) to afford the desired product (S)-2-methyl-4-methylidene-3-(2-propynyl)cyclopent-2-ene-1-ol (3.40 g, yield 81.0%) as a pale yellow oil.

Provenance & Evidence