Hydrochloric Acid → (1R*,5S*)-3-(4'-chloro-4-ethylbiphenyl-3-yl)-1-methyl-8-oxabicyclo[3.2.1]octane-2,4-dione

Participants

Reaction Conditions

Reaction Steps

To a mixture of chloroform (2.0 ml) and toluene (0.5 ml) is added (1R*,5S*)-1-methyl-8-oxa-bicyclo[3.2.1]octane-2,4-dione (0.10 g, 0.6 mmol) and N,N-dimethylamino-pyridine (0.395 g, 3.2 mmol) under a nitrogen atmosphere with stirring. To this reaction mixture is added 4′-chloro-4-ethylbiphenyl-3-yllead triacetate (0.42 g, 0.70 mmol) in one portion, then the mixture is heated at 80° C. for 1-2 hours. The reaction mixture is cooled to room temperature, acidified with dilute aqueous hydrochloric acid then filtered through diatomaceous earth to remove inorganic residues (subsequent washing with dichloromethane). The aqueous fractions are extracted with dichloromethane (2×5 ml), all organic fractions are combined, dried over sodium sulfate then concentrated under vacuum to give the crude product which is purified by flash chromatography (hexane/ethyl acetate) to give (1R*,5S*)-3-(4′-chloro-4-ethylbiphenyl-3-yl)-1-methyl-8-oxabicyclo[3.2.1]octane-2,4-dione (0.150 g) as a white solid.

Provenance & Evidence