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ChemicalBook CAS DataBase List Dimethyl methylphosphonate
756-79-6

Dimethyl methylphosphonate synthesis

14synthesis methods
-

Yield:756-79-6 96%

Reaction Conditions:

Stage #1:1,1,1-tri(hydroxymethyl)propane;phosphorous acid trimethyl ester at 80 - 120; for 4 h;
Stage #2: with methyl p-toluene sulfonate at 170 - 180; for 2 h;Reagent/catalyst;Temperature;

Steps:

1; 2 Example 1
Transesterification: When equipped with a magnetic stirrer, atmospheric distillation device (with packing column) and a 1000mL four-neck flask with a thermometer, Add 745g trimethyl phosphite and201g of trimethylolpropane was heated to 80-120°C, and the by-product methanol was separated by distillation while reacting. The column top temperature of the methanol fraction was 63-65°C, and the reaction distillation was carried out for 4 hours to obtain the transesterified product; Rearrangement: Replace the packed column with a reflux condenser to change the reaction distillation device into a reflux reaction device. Add 6g of the catalyst methyl p-toluenesulfonate into the reactor, stir, heat to 170180, keep the temperature and react for 2h to obtain the crude product; Vacuum distillation: transfer the crude product to a rotary evaporator, under a vacuum of 0.0950.1MPa and an oil bath temperature of 190200, rotary evaporate, collect 390g of dimethyl methylphosphonate, and cool the remainder. It is a product, 412g, with a yield of 96percent.

References:

Tsingtao Changrong Chemical Technology Co., Ltd.;Han Zhongshan;Han Mingxu;Yang Songhui CN111377967, 2020, A Location in patent:Paragraph 0030-0038

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