Dimethyl Sulfoxide → 2,2-Dimethyl-7-phenyl-7-pyridin-3-yl-hept-6-enoic acid

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

Sodium hydride (2.5 g, 60% oil dispersion) was washed with hexane, to make clean of the oil and dried under reduced pressure. Dimethylsulfoxide (25 ml) was added to it, and the mixture was heated under argon at 80° C. for 1 hour to produce dimsyl anions. The reaction solution was cooled at 10° C., and 5-carboxy-5,5-dimethylpentyltriphenylphosphonium bromide (8 g, 16 mmole) was added, followed by stirring at room temperature for another 10 minutes. A dimethylsulfoxide solution (5 ml) containing 3-benzoylpyridine (3 g, 16 mmole) was added dropwise to the mixture solution, and after the completion of the dropwise addition, stirring was continued at room temperature for 30 minutes. Water (50 ml) was added to the mixture, which was then shaken. The organic layer was separated, and the water layer was adjusted to pH 6.0 with 2N hydrochloric acid. The product was extracted three times with ethyl acetate (50 ml). The ethyl acetate layers were combined, washed with water, dried (over magnesium sulfate) and concentrated under reduced pressure. The residue was chromatographed on a column of silica gel, and development was effected with ethyl acetate to yield (E)+(Z)-2,2-dimethyl-7-phenyl-7-(3-pyridyl)-6-heptenoic acid (2-a, 2-b) (2.2. g).

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