反应详情

To a solution of 7,8-dimethyl-3,4-dihydrospiro[chromene-2,1′-cyclobutan]-6-ol (0.5 g) in 20 mL of dioxane under argon, was added borontrifluoride-diethyl etherate (0.72 mL) followed by geraniol (0.4 mL) and the reaction was stirred overnight. After addition of water, the solution was extracted with EtOAc, washed with brine, dried over Na2SO4, and evaporated. The residue was purified on a silica column eluting with 1:8 EtOAc/hexane to give 5-(3,7-dimethylocta-2,6-dienyl)-7,8-dimethylspiro[chroman-2,1′-cyclobutan]-6-ol (104 mg ) as an amber oil. 1H-NMR (300 MHz, CDCl3) δ=1.65-1.99 (m, 10H), 2.01-2.28 (m, 17H), 2.74-2.79 (t, 2H), 3.35-3.37 (d, H), 4.78 (s, 1H), 5.10-5.12 (t, 1H), 5.17-5.21 (t, 1H) ppm. 13C-NMR (75 MHz, CDCl3) δ=11.93, 12.15, 12.61, 16.21, 17.80, 20.47, 25.55, 25.80, 26.45, 29.58, 34.05, 39.74, 76.23, 117.15, 121.87, 121.97, 122.48, 123.62, 123.89, 132.02, 138.03, 145.52, 145.89 ppm. MS (m/z)=354 (M+H+).

1. extractionthe solution was extracted with EtOAc
2. washwashed with brine
3. dry with materialdried over Na2SO4
4. customevaporated
5. customThe residue was purified on a silica column
6. washeluting with 1:8 EtOAc/hexane