58446-52-9

112-61-8

98-86-2

58446-52-9

The general procedure for the synthesis of 1-phenylene eicosane-1,3-dione from methyl stearate and acetophenone is as follows: the experimental setup is a 1 liter volume classical glass double jacketed chemical engineering reactor equipped with an efficient mixing system. A separation column with variable reflux condenser was mounted on top of the reactor and a recirculation loop equipped with a gear pump and a 600 W microwave generator. First, 440 ml of xylene, 178.76 g of methyl sulfate and 42.87 g of powdered sodium methanol were added to the reactor. After the reagents were added, a continuous stream of nitrogen was used to inert the reactor's internal environment. The reaction mixture was circulated at a rate of 15 kg/h through an external loop. The mixture was allowed to boil and maintained at full reflux followed by activation of the microwave source. 68.45 g of acetophenone was slowly added over a period of 1 hour. After the addition of acetophenone was completed, the reaction was continued for 15 min, during which the generated methanol and ethanol were removed from the reaction mixture.After 15 min, the microwave source was switched off and the reaction mixture was heated to acidify the reaction mixture, followed by washing. Gas chromatographic analysis showed that acetophenone was almost completely consumed and the titer of 1-phenyloctane-1,3-dione was 98.3%. The production rate of 1-phenyleicosane-1,3-dione in the reaction stage was 173.2 kg-h?1-m?3.