Dimethyl Carbonate → Methyl 4-(4-Benzyloxyphenoxy)-3-oxopentanoate

Participants

Reaction Conditions

Reaction Steps

Into a 25 ml, three-necked round-bottom flask fitted with a thermometer, vigreux column, distillation head, magnetic stirrer, syringe pump and nitrogen sweep was charged 5.0 g of 3-(4-benzyloxyphenoxy)-2-butanone and 10 g of dimethyl carbonate, and the solution heated to 90° C. Thereafter, 2.0 ml sodium methoxide in methanol was added over a period of 50 minutes via a syringe pump. At the end of this addition, the reaction mixture was of a thick, cloudy orange consistency. It was then stirred for 40 minutes and charged with another 2.7 ml of sodium methoxide in methanol over a period of 30 minutes while distilling over methanol. At the end of the addition, the solution was very thick, and another 5 ml of dimethylcarbonate was added to improve the stirring capabilities. The solution was then removed from the heat, cooled to room temperature, and allowed to set for one hour. After this time, it was reheated to reflux temperature, and another 1.1 ml of sodium methoxide in methanol was charged over a period of 13 minutes. Fifteen minutes after the addition, the heat was removed, and the solution cooled to room temperature. The solution was then stripped to remove dimethyl carbonate and then mixed with 50 ml of ethyl acetate, 50 ml of ice water and 5 ml of acetic acid. The resulting mixture was shaken and separated and the organic phase was washed with 50 ml of water, and dried over magnesium sulfate. The solution was then filtered and stripped on an aspirator, yielding 5.75 g of a dark brown oil which was identified as being the subject compound by suitable analysis.

Provenance & Evidence