反应详情

2-(3-Benzyloxy-5-bromophenyl)malonic acid tert-butyl ester ethyl ester (7.2 g, contains 1.4 equivalent malonic acid tert-butyl ester ethyl ester, 10 mmol) was dissolved in glacial AcOH (50 ml) and heated to reflux for 12 h. The AcOH was removed under reduced pressure. The residue was poured into Na2CO3 solution (sat aq) and the mixture was extracted with EtOAc (×3). The combined organic extracts were washed with water, brine, dried (MgSO4), filtered and concentrated under reduced pressure to give (3-benzyloxy-5-bromo-phenyl-)acetic acid ethyl ester (6.8 g, 9.7 mmol) as a yellow liquid in 97% yield. 1H NMR (CDCl3) δ 7.44-7.30 (m, 5H), 7.07-7.03 (m, 2H), 6.87-6.84 (m, 1H), 5.03 (s, 2H), 4.15 (q, 2H), 3.54 (s, 2H), 1.26 (t, 3H).

1. temperatureheated
2. temperatureto reflux for 12 h
3. customThe AcOH was removed under reduced pressure
4. additionThe residue was poured into Na2CO3 solution (sat aq)
5. extractionthe mixture was extracted with EtOAc (×3)
6. washThe combined organic extracts were washed with water, brine
7. dry with materialdried (MgSO4)
8. filtrationfiltered
9. concentrationconcentrated under reduced pressure