Boron trifluoride etherate → HCID 10539699, compound

Participants

Reaction Steps

Six grams biphenylcarboxaldehyde, 10.23 g 5-carboxypentyl triphenylphosphorane bromide, 5.8 g anhydrous K2CO3 and 130 mg 18-Crown-6 were suspended in 240 mL dry tetrahydrofuran. The mixture was heated and stirred at reflux for 7 days, diluted with 200 mL H2O, extracted with EtOAc (5×200 mL). The EtOAc extract was dried (Na2SO4) and concentrated, the residue was taken up in methanol (200 mL) treated with 1 equivalent BF3.OEt2 and the methyl esters of the cis and trans acids separated by chromatography (yield 59%). The esters were hydrolyzed upon dissolving in MeOH (100 mL) and treatment with 1N NaOH (50 mL). Acidification resulted in precipitation of the corresponding acids cis-6-(4'-biphenyl)hex-5-enoic acid, m.p. 107°-109° and trans-6-(4'-biphenylyl)hex-5-enoic acid, m.p. 116°-118°.

Provenance & Evidence