Synthesis
Anhydrous tetrahydrofuran (540 mL), dimethyl carbonate (235.2 g, 2.61 mol) and sodium hydrogen (130.5 g, 3.263 mol, 60%) were added to a dry reaction flask then the mixture was heated to reflux, and a solution of anhydrous tetrahydrofuran (180 mL) of p-fluoroacetophenone (180.3 g, 1.305 mol) was slowly added dropwise, the dropwise addition process was titrated over a period of 4 hours. Refluxing of the reaction solution was continued for another 0.5 h. The reaction was monitored by TLC (ethyl acetate:petroleum ether v/v=1:6, Rf=0.3) and the reaction solution was cooled to 0C. Excess sodium hydroxide was quenched dropwise by addition of a mixture of 90 ml of methanol and 270 ml of tetrahydrofuran. The reaction solution was poured into a mixture of saturated ammonium chloride and ice, hydrochloric acid adjusted pH = 3,ethyl acetate, respectively, washed with water, saline, drying, concentrated under reduced pressure to obtain the crude product (292.9 g.100%) oil.
