反应详情

A solution of ethyl 3-cyclopentyl-2-(cyclopentylcarbonyl)-3-oxopropanoate (2.20 g, 7.84 mmol) in EtOH (6.4 mL) was stirred as water (1.2 mL) followed by hydroxylamine hydrochloride (1.02 g, 14.7 mmol) was added. The solution was then heated to reflux for 3 hours. The solution was concentrated and the residue was partitioned between ether and saturated aqueous NaHCO3 solution. The organic layer was washed with brine, dried with MgSO4, filtered and concentrated to yield ethyl 3,5-dicyclopentyl-4-isoxazolecarboxylate as a yellow oil (1.58 g, crude yield 73%). 1H NMR (400 MHz, DMSO-d6): δ 4.23 (q, J=7 Hz, 2H), 3.78-3.72 (m, 1H), 3.45-3.37 (m, 1H), 2.00-1.92 (m, 4H), 1.83-1.49 (m, 12H), 1.26 (t, J=7 Hz, 3H). ESI-LCMS m/z 278 (M+H)+.

1. additionwas added
2. temperatureThe solution was then heated
3. temperatureto reflux for 3 hours
4. concentrationThe solution was concentrated
5. customthe residue was partitioned between ether and saturated aqueous NaHCO3 solution
6. washThe organic layer was washed with brine
7. dry with materialdried with MgSO4
8. filtrationfiltered
9. concentrationconcentrated