反应详情

In a 200 ml pear flask were added methyl 4-bromo-3-hydroxybenzoate (3.5 g, 15 mmol), potassium carbonate (4.2 g, 30 mmol) and tetrabutylammonium iodide (0.084 g, 0.23 mmol) in DMF (35 ml) to give a suspension. At 0° C. was added 3-bromo-2-methylprop-1-ene (1.7 ml, 17 mmol) to this mixture, which was then stirred at room temperature for ˜16 h. The reaction mixture was partitioned between brine and ether, and the aqueous layer was extracted one more time with ethyl acetate. Combined organic layers were washed with brine, dried over MgSO4, filtered and concentrated to give the crude product methyl 4-bromo-3-(2-methylallyloxy)benzoate (4.3 g, 99% yield) as a light yellow oil. 1H NMR (CHLOROFORM-d) δ: 7.61 (d, J=8.1 Hz, 7H), 7.53 (d, J=1.5 Hz, 7H), 7.50 (dd, J=8.1, 1.8 Hz, 7H), 5.20 (d, J=1.0 Hz, 7H), 5.02-5.07 (m, 7H), 4.56 (s, 2H), 3.92 (s, 3H), 1.87 (s, 3H); ESI-MS: m/z 242.3 (M+H)+.

1. customto give a suspension
2. customThe reaction mixture was partitioned between brine and ether
3. extractionthe aqueous layer was extracted one more time with ethyl acetate
4. washCombined organic layers were washed with brine
5. dry with materialdried over MgSO4
6. filtrationfiltered
7. concentrationconcentrated