Method for synthesizing dimethyl methylphosphonate

Abstract

A method for synthesizing dimethyl methylphosphonate. Under protection of inert gas, A raw material trimethyl phosphite and a proper amount of benzene sulfonic acid catalyst are mixed and stirred; and a the mixture is subjected to a rearrangement reaction through a pressurized heating way, so as to synthesize a target product dimethyl methylphosphonate with yield up to 93% and purity higher than 99%. The invention has advantages of easily available raw materials, short synthesis time, simple production control, cheap and recyclable catalyst and little pollutant emission.

Description

technical field [0001] The invention belongs to the synthesis technology of alkyl phosphate ester compounds, and in particular relates to a preparation method capable of industrially producing dimethyl methyl phosphate. Background technique [0002] Plastic products have been widely used in construction, transportation, aviation, electrical appliances, household furniture and other fields, and these plastic products often need to be flame retardant. DMMP has high phosphorus content, excellent flame retardant performance, good solubility, miscible with water and various organic solvents or polymers; low viscosity, can also be used as a viscosity inhibitor; colorless and transparent, can be made into transparent or brightly colored Flame retardant products; small acid value of moisture, does not affect other properties of flame retardant products; small amount of addition, can greatly reduce product cost, low toxicity, non-corrosive, wide application range, suitable for variou...

AI Technical Summary

Problems solved by technology

[0005] 2. Using dimethyl phosphite or dimethyl hypophosphite as a raw material synthesis method, dimethyl phosphite or dimethyl hypophosphite and methyl iodide undergo Michaelis-Becker reaction to obtain dimethyl methyl phosphate (Bulletin of the Academy of Sciences of the USSR, Division of Chemical Science (English Translation), 37:1744,1988; Phosphorus, Sulfur and Silicon and the Related Elements, 185(9):1845-1849, 2010; Phosphorus Sulfur and Silicon and the Related Elements, 181(3):511-518, 2006; Physical Chemistry Chemical Physics, 4(11): 2200-2205, 2002; Bulletin of the Academy of Sciences of the USSR, Division of Chemical Science (English Translation), 39 (5): 1076,1990); Using diazomethane as a methylating reagent can also convert dimethyl phosphite or dimethyl hypophosphite into dimethyl phosphate (Phosphorus, Sulfur and Silicon and the Related Elements , 73(1-4): 153 – 160, 1992) , and it was also reported that the target compound (PCT Int . Appl., 2008154268, 2008), the methylation reagent price of this kind of method is higher, and the production cost is higher than trimethyl phosphite synthetic method

[0008] 5. Using dimethyl methyl phosphite as a raw material synthesis method, dimethyl methyl phosphite can be synthesized by reacting dimethyl methyl phosphite with tertiary peroxyalcohol for 10 min at room temperature (Tetrahedron Letters, 26(22) : 2649 – 2652,1985), but the cost of this method is too high to be suitable for industrial production

[0009] The above-mentioned synthetic techniques have their own characteristics, but these methods often have shortcomings such as some methods have a longer reaction time, some raw materials or catalysts are too expensive, and some catalysts or reagents are highly toxic. The preparation process with the advantages of short reaction time, high yield, easy access to raw materials, low production cost, and less pollution is meaningful