Toluene → 2-Propenoic acid, 2-methyl-, 2-(2-propen-1-yloxy)ethyl ester

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a three-necked flask equipped with a stirrer, a thermometer, a reflux condenser and a Dean-Stark apparatus were added methacrylic acid (137.7 g, 1.6 moles), ethyleneglycol monoallylether (80.7 g, 0.8 moles), p-toluenesulfonic acid (0.76 g, 4.0 mmole) and toluene (650 mL). The mixture was heated to 120° C. for 5 hours with exclusion of water. Another portion of p-toluenesulfonic acid (0.12 g) and the mixture was heated to 120° C. for 6 hours. The other portion of p-toluenesulfonic acid (0.1 g) was added and the mixture was heated to 120° C. for 9 hours. During the reaction, the consumption of methacrylic acid and ethyleneglycol monoallylether were monitored by liquid chromatography and the conversion reached 98%. The mixture was neutralized by addition of aq. NaHCO3 and the layers were separated. The aqueous layer was extracted with toluene and the combined organic layers were dried over CaCl2 and concentrated under reduced pressure. Distillation of the crude material (60° C. at 2 mmHg) yielded 2-allyloxyethyl methacrylate (98.7 g, 73%) shown below.

Herkunft & Nachweise