Ethylene Glycol → (S)-6-Ethyl-1,4-dioxaspiro[4.5]decane-6-propanoic Acid, 2-Hydroxyethyl Ester

Participants

Reaction Steps

(S)-1-Ethyl-2-oxocyclohexanepropanoic acid (605 g), and ethylene glycol (14.6 mol, 906 g, 814 mL) were refluxed in 1.5 L of toluene containing 10 g of p-toluenesulfonic acid with azeotropic removal of water. After 56 hours, water stopped coming off. The reaction was diluted with 1 L of toluene and washed with water (2×500 mL), saturated sodium bicarbonate (aq) (2×500 mL), and brine (500 mL). Drying (magnesium sulfate) and concentration afforded 942 g of clear yellow oil which was used as in the next step.

Provenance & Evidence