Diethylene Glycol Monomethyl Ether → Carbonic acid, 2-(2-methoxyethoxy)ethyl methyl ester

Participants

Reaction Conditions

Reaction Steps

A total of 144.2 grams (1.2 mol) of 2-(2-methoxyethoxy)ethanol, 400 grams (4.4 mol) of dimethyl carbonate and 3 grams (0.05 mol) of sodium methoxide were combined in a 1-liter 3-neck round bottom flask equipped with a 14 inch distillation column, distillation head, and magnetic stirbar. The system was evacuated and purged three times with nitrogen using a Firestone valve, and left under a constant nitrogen atmosphere. After a period of 1.5 hours at reflux (kettle temperature 84° C.), methanol (boiling point 64° C.) was slowly removed overhead to drive the equilbrium. A total of 49.8 grams of methanol was removed over a period of 3 hours, after which time the stopcock was closed and the reaction mixture was allowed to reflux overnight. The mixture was then cooled to room temperature, filtered and charged (429 grams) to a 500 milliliter round bottom flask equipped with a distillation head and magnetic stirbar. Excess dimethyl carbonate (boiling point 90° C.) was removed overhead. The flask was then cooled, put under vacuum (10-11 mm Hg , and methyl 2-(2-methoxyethoxy)ethyl carbonate removed overhead (boiling point 115°-125° C.). A total of 193 grams (ca. 90% yield) was obtained. Gas chromatography analysis of this material showed 97.74% purity (remainder was 2-(2-methoxyethoxy)ethanol).

Provenance & Evidence