Benzaldehyde → HCID 13479258, Verbindung

Reaktionsgleichung

[Br-].[CH2:2]([O:4][C:5]([CH2:7][CH2:8][CH2:9][P+](CC)(CC)CC)=[O:6])[CH3:3].[CH:17](=O)[C:18]1[CH:23]=[CH:22][CH:21]=[CH:20][CH:19]=1.CC(C)([O-])C.[K+]>CC(OC)(C)C>[C:18]1(/[CH:17]=[CH:9]\[CH2:8][CH2:7][C:5]([O:4][CH2:2][CH3:3])=[O:6])[CH:23]=[CH:22][CH:21]=[CH:20][CH:19]=1

Komponenten

Versuchsvorschrift

3-Ethoxycarbonylpropyltriethylphosphonium bromide (5.488 g, 12.00 mmol), benzaldehyde (3.820 g, 36.00 mmol) and potassium tert-butoxide (4.040 g, 36.00 mmol) were taken up in MTBE (300 mL) at room temperature and was stirred overnight. The reaction mixture was washed with water (1×100 mL) and the aqueous phase was extracted with MTBE (3×100 mL). Solvent was removed from the combined organic phase under reduced pressure and the resulting oil purified by column chromatography (0-10% EtOAc/n-hexane, silica) to give (Z)-ethyl 5-phenylpent-4-enoate as a pale yellow oil. 1H NMR (CDCl3): δ 7.36-7.31 (m, 2H), 7.28-7.21 (m, 3H), 6.47 (d, 1H, J=11.6, Ph-CH), 5.63 (dt, 1H, J1=11.6, J2=7.2), 4.14 (q, 2H, J=7.2), 2.66 (dq, 2H, J1=7.3, J2=1.7), 2.43 (t, 2H, J=7.6), 1.24 (t, 3H, J=7.1). Contains ca. 33% (E)-ethyl 5-phenylpent-4-enoate