反应详情

To a stirred solution of methyl 3,5-dihydroxybenzoate (0.1 mol) in DMF (180 mL) was added powdered potassium carbonate (0.2 mol) and 2-iodopropane (0.1 mol), and the resulting mixture stirred at ambient temperature for 16 hours. The reaction mixture was poured into water (1000 mL) and the mixture extracted with ether. The extracts were combined and washed sequentially with water (twice) and brine; the solution was dried (MgSO4), filtered and evaporated in vacuo to give the crude product as a pale yellow oil (12.6 g). This was treated with toluene (40 mL) and allowed to stand overnight. The insoluble material (starting phenol) was removed by filtration, and the filtrate evaporated in vacuo. The resulting oil was chromatographed (2×90 g Biotage silica cartridges), eluting with hexane containing ethyl acetate (10% increasing to 15% v/v). The title compound was obtained as an oil (25% yield), which was identical by tlc to a sample prepared by a similar procedure. 1H NMR δ (d6-DMSO): 1.2 (d, 6H), 3.8 (s, 3H), 4.5-4.6 (hept, 1H), 6.55 (m, 1H), 7.85 (m, 1H), 7.95 (m, 1H), 9.8 (s, 1H)

1. extractionthe mixture extracted with ether
2. washwashed sequentially with water (twice) and brine
3. dry with materialthe solution was dried (MgSO4)
4. filtrationfiltered
5. customevaporated in vacuo
6. customto give the crude product as a pale yellow oil (12.6 g)
7. waitto stand overnight
8. customThe insoluble material (starting phenol) was removed by filtration
9. customthe filtrate evaporated in vacuo
10. customThe resulting oil was chromatographed (2×90 g Biotage silica cartridges)
11. washeluting with hexane
12. additioncontaining ethyl acetate (10%
13. temperatureincreasing to 15% v/v)