Hydrochloric Acid → 4,7-Ethano-2H-isoindole-1-carboxylic acid, 4,7-dihydro-, ethyl ester

Participants

Reaction Conditions

Reaction Steps

The reaction system of a mixed solution of 7.76 g (20 mmol) of the resultant 5,6-bis(phenylsulfonyl)-bicyclo[2.2.2]octa-2-ene and 50 ml of anhydrous tetrahydrofuran was replaced with nitrogen. Then, 2.425 ml (22 mmol) of ethyl isocyanoacetate were added to the solution, and the mixture was cooled to 0° C. Potassium t-butoxide (50 ml/1 M THF (tetrahydrofuran) solution) was dropped over 2 hours, and the whole was stirred at room temperature for 3 hours. After the completion of the reaction, dilute hydrochloric acid was added, and then the reaction mixture was washed with a saturated aqueous solution of sodium hydrogen carbonate, distilled water, and a saturated salt solution in this order, followed by drying with anhydrous sodium sulfate. The dried product was purified by means of silica gel column chromatography (chloroform) to yield ethyl-4,7-dihydro-4,7-ethano-2H-isoindole-1-carboxylate (3.5 g, 16 mmol, 80% yield).

Provenance & Evidence