反应详情

温度

110 °C

(The procedure described for the trans isomer in JCS Perkin I, 1999, 25, 3023 was used.) A mixture of cis-cyclohexane-1,4-dicarboxylic acid (TCI) (24.1 g, 140 mmol), butyl formate (700 ml, 623 g, 6.10 mol, 43.5 equiv.), and Dowex 50W×2 resin (50-100 mesh, 140 g) in octane (700 ml) was stirred under nitrogen in a 110° C. oil bath for 24 hours. The mixture was cooled to ambient temperature. The supernatant solution was decanted away from the resin. The resin was washed with ethyl acetate: hexane (1:1, five 150 ml portions), and the washings were added to the supernatant. The solution was evaporated under reduced pressure, the resulting residue diluted with toluene (25 ml), evaporated under reduced pressure, and dried to give crude cis-4-(butoxycarbonyl)cyclohexanecarboxylic acid (36.5 g) as a yellow oil: 1H NMR (CDCl3) 4.08 (2H, m), 2.53 (1H, m), 2.46 (1H, m), 1.92 (4H, m), 1.70 (4H, m), 1.61 (2H, m), 1.38 (2H, m), 0.93 (3H, t, J 7 Hz).

1. temperatureThe mixture was cooled to ambient temperature
2. customThe supernatant solution was decanted away from the resin
3. washThe resin was washed with ethyl acetate: hexane (1:1, five 150 ml portions)
4. additionthe washings were added to the supernatant
5. customThe solution was evaporated under reduced pressure
6. additionthe resulting residue diluted with toluene (25 ml)
7. customevaporated under reduced pressure
8. customdried