Triethyl phosphonoacetate → ethyl (2E)-3-cyclopropylacrylate

Temperatur

0 °C

To a stirred suspension of NaH (60% in oil, 2.1 g, 51.5 mmol) in dry THF (50 mL) was added dropwise ethyl(diethoxyphosphoryl)acetate (10.6 g, 47.1 mmol) at 0° C. under N2 atmosphere. The resulting mixture was stirred at 0° C. for 0.5 hr and added dropwise a solution of cyclopropanecarbaldehyde (3.0 g, 42.9 mmol) in dry THF (50 mL). After the addition, the mixture was stirred at rt for 16 hrs. Then the reaction mixture was quenched by addition of 5% NH4Cl (100 mL) at 0° C. and extracted with EtOAc (100 mL). The organic layer was washed with brine (100 mL), dried over Na2SO4 and concentrated in vacuo. The residue was purified by column chromatography (silica gel, petroleum ether: EtOAc=30:1) to give the title compound (5.3 g, 88.3% yield) as a colorless oil.

1. additionAfter the addition
2. stirringthe mixture was stirred at rt for 16 hrs
3. customThen the reaction mixture was quenched by addition of 5% NH4Cl (100 mL) at 0° C.
4. extractionextracted with EtOAc (100 mL)
5. washThe organic layer was washed with brine (100 mL)
6. dry with materialdried over Na2SO4
7. concentrationconcentrated in vacuo
8. customThe residue was purified by column chromatography (silica gel, petroleum ether: EtOAc=30:1)

ORD-Eintrag

ord-0d5099fee21443f498ffa643cf058d1f

Quelldatensatz

uspto-grants-2015_05

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US09040547B2