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

Participants

Reaction Conditions

Reaction Steps

A 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 mixed solution, and the whole was cooled to 0° C. Potassium tert-butoxide (50 ml/l M THF solution) was dropped into the mixture in 2 hours, and the whole was stirred at room temperature for 3 hours. After the completion of the reaction, diluted hydrochloric acid was added to the reaction mixture. Then, the reaction mixture was washed with a saturated aqueous solution of sodium hydrogen carbonate, distilled water, and a saturated aqueous solution in this order, and was dried 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