2-Pyridinecarboxaldehyde → 7-(2-Pyridyl)-6-heptenoic acid

Beteiligte Stoffe

Reaktionsschritte

(5-Carboxypentyl)triphenyl phosphonium (13.7 g, 30.0 mmol) was suspended in tetrahydrofuran (50 ml), and potassium tert-butoxide (6.3 g, 56.0 mmol) was added thereto under ice cooling condition. The mixture was stirred for 1 hr. Successively, a solution of 2-pyridinecarbaldehyde (2.0 g, 18.7 mmol) in tetrahydrofuran (10 ml) was added to the mixture, and the mixture was stirred at 0° C. for 3 hrs. The reaction mixture was combined with 2 N aqueous sodium hydroxide solution (50 ml), washed with diethyl ether, neutralized with 6 N HCl and extracted with ethyl acetate. The organic layer was washed with saturated brine and dried over magnesium sulfate. The solvent was evaporated, and the residue was subjected to a silica gel (100 g) column chromatography. The fractions eluted with hexane-ethyl acetate (1:1, v/v) were collected and concentrated to give Z-form of the titled compound (2.0 g, 52%). And the fractions eluted with hexane-ethyl acetate (1:2, v/v) were collected and concentrated to give a mixture of E-form and Z-form of the titled compound (0.97 g, 25%)

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