Ethyl 4-oxocyclohexanecarboxylate → Ethyl 4-methylidenecyclohexane-1-carboxylate

Temperature

0 °C

To a solution of (methyl)triphenylphosphonium bromide (5.18 g, 14.51 mmol) in THF (50 mL) at 0° C. was added n-butyllithium (9.07 mL, 14.51 mmol). The reaction mixture was stirred at 0° C. for 30 min. Ethyl 4-oxocyclohexanecarboxylate (1.9 g, 11.16 mmol) in THF (8 mL) was then added at 0° C. and the reaction was warmed to rt and stirred for 2 h. The reaction was quenched with sat′d aq. NH4Cl and diluted with EtOAc. The organic layer was washed with water and brine, dried over MgSO4, filtered, and concentrated in vacuo. The residue was purified by flash chromatography on SiO2 (0 to 50% EtOAc:hexanes) to afford the title compound (1.58 g, 84% yield) as a colorless oil. 1H NMR (500 MHz, CDCl3) δ 4.65 (s, 2H), 4.17-4.11 (m, 2H), 2.44 (tt, J=11.1, 3.8 Hz, 1H), 2.35 (dt, J=13.7, 4.0 Hz, 2H), 2.11-1.96 (m, 4H), 1.64-1.54 (m, 2H), 1.28-1.23 (m, 3H).

1. temperaturethe reaction was warmed to rt
2. stirringstirred for 2 h
3. customThe reaction was quenched with sat′d aq. NH4Cl
4. additiondiluted with EtOAc
5. washThe organic layer was washed with water and brine
6. dry with materialdried over MgSO4
7. filtrationfiltered
8. concentrationconcentrated in vacuo
9. customThe residue was purified by flash chromatography on SiO2 (0 to 50% EtOAc:hexanes)

ORD record

ord-4d0d3d6f13524225987316372bc0f1f6

Source dataset

uspto-grants-2015_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08962660B2