反应详情

A 250 mL one neck round bottomed flask equipped with a reflux condenser, nitrogen inlet and provisions for magnetic stirring was charged with ethyl trifluoroacetate (28.4 g, 0.2 mol) and 75 mL of ether. To this solution was added 48 mL of 25% sodium methoxide in methanol (0.21 mol). A solution of 1-tetralone (29.2 g, 0.2 mol) in ether (50 mL) was added over about 5 minutes The reaction mixture was stirred at room temperature for 14 hours and was diluted with 100 mL of 3N HCl. The phases were separated, and the organic layer was washed with 3N HCl and with brine, dried over anhydrous MgSO4, filtered and concentrated in vacuo. The residue was taken up in 70 mL of boiling ethanol/water and cooled to room temperature, whereupon crystals of 3,4-dihydro-2-[2,2,2-trifluoro-1-hydroxyethylidene]-1(2H)-naphthalenone formed which were isolated by filtration and air dried to give 32 g (81%) of pure 3,4-dihydro-2-[2,2,2-trifluoro-1-hydroxyethylidene]-1(2H)-naphthalenone: mp 48°-49° C.; 1H NMR (CDCl3) δ 2.8 (m, 2H), 2.9 (m, 2H), 7.2 (d, j=3.0 Hz, 1H), 7.36 (m, 1H), 7.50 (m, 1H), 7.98 (m, 1H); 19F NMR (CDCl3) δ-72.0. EI GC-MS M+ =242.

1. stirringwas stirred at room temperature for 14 hours
2. customThe phases were separated
3. washthe organic layer was washed with 3N HCl and with brine
4. dry with materialdried over anhydrous MgSO4
5. filtrationfiltered
6. concentrationconcentrated in vacuo
7. customformed which
8. customwere isolated by filtration and air
9. customdried