Ethyl adipate (CAS NO.: ), which is also known as Ethyl hydrogen adipate, could be produced through the following synthetic routes.

Four hundred thirty-eight grams (3 moles) of adipic acid, 1080 cc. (9 moles) of absolute alcohol, 540 cc. of toluene, and 2.5 cc. of concentrated sulfuric acid (Note 1) are placed in a 3-l. distilling flask. The flask is connected with a downward condenser and heated on an oil bath. An azeotropic mixture of alcohol, toluene, and water begins to distil at 75°. Distillation is continued until the thermometer in the neck of the flask rises to 78°, when further heating is suspended.

The distillate is collected in a 2-l. flask containing 450 g. of anhydrous potassium carbonate. It is well shaken, filtered through a Büchner funnel, and returned to the distilling flask. The flask is again heated until the temperature rises to 78–80°, when distillation is discontinued. The residual liquid is emptied into a 1-l. flask, the large flask being rinsed with a little alcohol, and distilled under vacuum. Alcohol and toluene distil first; then the temperature rises and ethyl adipate distils at 138°/20 mm.. The yield is 580 to 588 g. (95–97 per cent of the theoretical amount).