Diisobutylaluminum hydride → (Z)-5-phenylpent-4-enal

Temperature

-78 °C

(Z)-Ethyl 5-phenylpent-4-enoate (1.600 g, 7.833 mmol) was taken up in dichloromethane (100 mL) under N2 and chilled to −78° C. DIBAL (1M in hexanes, 9 mL, 9.0 mmol) was added and the reaction mixture was stirred at −78° C. for 3 hours. The excess DIBAL was quenched with the slow addition of methanol (25 mL). The resulting solution was poured into a saturated solution of sodium/potassium tartarate (400 mL). Further hexane (150 mL) was added and the mixture was stirred at room temperature over night. The organic phase was collected and solvent removed under reduced pressure. The resulting oil was purified by column chromatography (0–20% EtOAc/n-hexane, silica) to give (Z)-5-phenylpent-4-enal as a pale yellow oil. 1H NMR (CDCl3): δ 9.77 (s, 1H), 7.36–7.29 (m, 2H), 7.25–7.21 (m, 3H), 6.49 (d, 1H, J=11.5), 5.62 (dt, 1H, J1=11.6, J2=7.2, Ph-CHCH), 2.70–2.62 (m, 2H), 2.60–2.55 (m, 2H). Contains ca. 16% (E)-5-phenylpent-4-enal.

1. customThe excess DIBAL was quenched with the slow addition of methanol (25 mL)
2. additionThe resulting solution was poured into a saturated solution of sodium/potassium tartarate (400 mL)
3. additionFurther hexane (150 mL) was added
4. stirringthe mixture was stirred at room temperature over night
5. customThe organic phase was collected
6. customsolvent removed under reduced pressure
7. customThe resulting oil was purified by column chromatography (0–20% EtOAc/n-hexane, silica)

ORD record

ord-cd747b0aaaec498f8da60a398394f998

Source dataset

uspto-grants-2007_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07241792B2