反应详情

A solution of 7'-ethynyl-3',4'-dihydrospiro[1,3-dioxolane-2,2'(1'H)-naphthalene] (0.85 g, 3.9 mmol) in THF (15 ml) and 1N HCl (5 ml) was stirred overnight at room temperature. Concentrated HCl (2×0.5 ml) was then added in two aliquots 2 hours apart. After stirring a further 2 hours the solution was diluted with diethyl ether, the aqueous phase was separated, and the solution dried (MgSO4) and concentrated in vacuo. The residue was purified by chromatography on silica gel (15 g) eluting with diethyl ether:hexane (1:9→1:4) to give 7-ethynyl-2-tetralone as a solid (0.31 g). 1H NMR (CDCl3, 200 MHz) δ: 2.54 (t, J=7 Hz, 2H, CH2), 3.05 (s, 1H, ethynyl H), 3.06 (t, J=7 Hz, 2H, CH2), 3.56 (s, 2H, CH2), 7.18 (d, J=8 Hz, 1H, Ar), 7.26 (s, 1H, Ar), 7.34 (d, J=8 Hz, 1H, Ar).

1. customthe aqueous phase was separated
2. dry with materialthe solution dried (MgSO4)
3. concentrationconcentrated in vacuo
4. customThe residue was purified by chromatography on silica gel (15 g)
5. washeluting with diethyl ether:hexane (1:9→1:4)