Acetaldehyde → 2-Propenal, 3-cyclopentyl-, (2E)-

Temperature

80 °C

To a stirred suspension of triphenylphosphoranylidene)acetaldehyde (27, 62.75 g, 200.0 mmol, 1.0 equiv) in anhydrous benzene (400 mL, 4476 mmol) was added cyclopentanecarbaldehyde (26, 21.36 mL, 200.0 mmol) at room temperature. The resulting reaction mixture was then heated at 80° C. for 16 h. When TLC and HPLC showed that the reaction was deemed complete, the reaction mixture was concentrated under reduced pressure. The residue was then directly purified by Combiflash (SiO2) with 0-10% EtOAc/hexane gradient elution to afford (2E)-3-cyclopentylacrylaldehyde (28, 14.4 g, 24.84 g theoretical, 58% yield) as a yellow oil. For 28: 1H NMR (DMSO-d6, 400 MHz) δ ppm 1H NMR (CDCl3, 400 MHz) δ 9.49 (d, 1H, J=7.8 Hz), 6.82 (dd, 1H, J=15.6, 7.8 Hz), 6.08 (dd, 1H, J=15.6, 8.0 Hz), 2.72 (m, 1H), 1.89 (m, 2H), 1.67 (m, 4H), 1.44 (m, 2H); C8H12O (MW, 124.18) LCMS (EI) m/e 125 (M++H).

1. customThe resulting reaction mixture
2. concentrationthe reaction mixture was concentrated under reduced pressure
3. customThe residue was then directly purified by Combiflash (SiO2) with 0-10% EtOAc/hexane gradient elution

ORD record

ord-ea7e99c80cd347c4b36302a6a8868cd0

Source dataset

uspto-grants-2016_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09290506B2