反应详情

To 6.0 g of 5-(tert-butyl)-2-hydroxybenzoic acid methyl ester in a round bottom flask was added tetrabutyl-ammoniumhydroxide 40% solution (7.45 g, 1 eq). The resulting solution was stirred at room temperature for 2 hr. All water was evaporated under reduced pressure and then in vacuo. To remove trace water, the salt was dried in a vacuum oven overnight and yielded 12.9 g (99%). To a solution of 12.9 g of tetra-butylammonium salt in 50 ml dry THF was slowly added methyliodide (3.61 mL, 2 eq). The resulting solution was stirred at room temperature for 2 hr. After the reaction was completed, the product was filtered out using ammonium iodide salt and washed with ethylacetate twice. The pH was adjusted to pH=2–3 using 1M HCl solution. This organic layer was collected by extraction with ethylacetate and water three times. The organic layer was dried over anhydrous magnesium sulfate (MgSO4). The organic layer was evaporated and the residue was purified by column chromatography (ethylacetate:hexane=1:5) (yield: 3.8 g, 60.0%) 1H NMR (CDCl3, 300 MHz): δ 1.30 (s, 9H), 3.86 (s, 3H), 3.90 (s, 3H), 6.90 (d, J=10.5 Hz, 1H), 7.47 (d, J=9.0 Hz, 1H), 7.82 (s, 1H).

1. customAll water was evaporated under reduced pressure
2. customTo remove trace water
3. customthe salt was dried in a vacuum oven overnight
4. customyielded 12.9 g (99%)
5. stirringThe resulting solution was stirred at room temperature for 2 hr
6. filtrationthe product was filtered out
7. washwashed with ethylacetate twice
8. customThis organic layer was collected by extraction with ethylacetate and water three times
9. dry with materialThe organic layer was dried over anhydrous magnesium sulfate (MgSO4)
10. customThe organic layer was evaporated
11. customthe residue was purified by column chromatography (ethylacetate:hexane=1:5) (yield: 3.8 g, 60.0%) 1H NMR (CDCl3, 300 MHz): δ 1.30 (s, 9H), 3.86 (s, 3H), 3.90 (s, 3H), 6.90 (d, J=10.5 Hz, 1H), 7.47 (d, J=9.0 Hz, 1H), 7.82 (s, 1H)