Ethanol → Calcium decanoate

Participants

Reaction Steps

To a one-liter three-necked flask equipped with a thermometer, mechanical stirrer, and a reflux condenser, were added decanoic acid (20.0 g, 116 mmole) and absolute ethanol (0.19 L). The mixture was stirred vigorously for 5 minutes. The clear solution was then diluted with water (30 ml). Solid calcium carbonate (5.5 g, 55 mmole) was added in one portion and the resulting white suspension heated under reflux for 12 days. Water (10 ml) was added to the reaction each day except the last one. On the last day, excess water (100 ml) was added to complete the reaction. The mixture was cooled to 45° C. (water bath) and filtered through a coarse glass funnel. This gave a white solid which was washed with absolute ethanol (50 ml), tert-butyl methyl ether (2×50 ml) and air-dried for 2 hours. The solid was then dissolved in boiling methanol (1.3 L) and the cloudy solution filtered on a Celite pad. The clear filtrate was cooled and concentrated to 300 ml. The white precipitate was filtered under suction (water aspirator) using a coarse glass funnel (1 L) and air-dried for 3 hours. The resulting solid was kept under high vacuum at 20° C. for 18 hours. The pure acid calcium salt was isolated as a snow-white solid. Yield of product: 14.0 g (63%); mp=172-76° C., 1H NMR (CD3OD, 400 MHz) δ: 2.18 (t, J=7.63 Hz, 4H); 1.61 (m, 4H); 1.30 (m, 24H); 0.91 (t, J=7.04 Hz, 6H); 13C NMR (D2O, 400 MHz) δ: 183.0, 38.0, 32.4, 30.2, 30.1, 30.0, 29.8, 26.9, 23,1, 13.9.

Provenance & Evidence