反应详情

To a solution of cyclobutanecarboxylic acid (50 g, 500 mmol) in EtOH (1.2 L) was slowly added H2SO4 (20 mL) at room temperature. The solution was stirred at reflux overnight, and then cooled and poured into H2O. The aqueous layer was extracted with ether. The combined organic layers were washed with brine, dried over Na2SO4, and concentrated in vacuo to give ethyl cyclobutanecarboxylate as a colorless oil (44 g, 69%). 1H NMR (400 MHz, CDCl3-d3) δ 4.04 (q, 2H), 3.04 (m, 1H), 2.12 (m, 4H), 1.88 (m, 2H), 1.18 (t, 3H).

1. customat room temperature
2. temperatureat reflux overnight
3. temperaturecooled
4. extractionThe aqueous layer was extracted with ether
5. washThe combined organic layers were washed with brine
6. dry with materialdried over Na2SO4
7. concentrationconcentrated in vacuo