Method for producing N-alkyl substituted phosphoric triamide

Abstract

The invention provides a method for producing N-alkyl substitution phosphoryl triamide, which comprises the following steps: phosphorus chloride liquid is mixed with at least one organic solvent for precooling, then alkylamine solution is added drop by drop, and the reaction temperature ranging from 10 to 12 DEG C is kept; refluxing through heating is performed after adding drop by drop until the reaction is completed; after the reaction feed solution is washed and an organic layer is dried through dryer, ammonia gas is pumped in the next reaction; the pumping speed of ammonia gas is controlled, and the temperature of a reaction system is kept within 10 to 30 DEG C until the reaction is completed; generated solid in the reaction system is separated; the obtained organic layer is distilled to remove most solvent after being washed and separated; residue is a crude product that is N-alkyl substitution phosphoryl triamide containing a formula (1), and the crude product is recrystallized so as to obtain a fine product, the purity quotient of which is more than 98 percent. Compared with other prior arts, the method has the characteristics that the reaction condition is mild, the technology is simple, the cost is low, the purity quotient of the product is high, etc., and the method is particularly suitable for industrialized production.

Description

technical field [0001] The invention relates to a preparation method of N-alkyl substituted phosphoric triamide, in particular to a production method of N-alkyl substituted phosphoric triamide. Background technique [0002] N-Alkyl-substituted phosphoric triamides are highly effective urokinase inhibitors. At present, urea, which is the most widely used in the world, must be converted into ammonium carbamate through the enzymatic hydrolysis of urokinase in the soil, and absorbed by plants in the form of ammonium nitrogen. Due to the high activity of urokinase in the soil, the rate of converting urea to release ammonium nitrogen is very fast, and before the crops can absorb it, they will be volatilized and lost as ammonia nitrogen. Some of the ammonium nitrogen that is not absorbed by crops can also be converted into nitrate nitrogen, which will cause the deterioration of the atmosphere and soil environment through leaching and volatilization. N-alkyl substituted phosphoric...

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Problems solved by technology

At present, there are few bibliographical reports on the production method of N-n-butylthiophosphoric triamide. Existing patents US5770771, US5883297 and DE102005053541 involve low-temperature reactions in the reported production process, or require a certain degree of vacuum, or The reaction that requires a certain pressure requires high production conditions. Triethylamine is used as an acid-binding agent in the production process, which increases the difficulty of separation. In addition, the amount of ammonia used is large, resulting in a certain degree of waste of resources. It needs to be used in the final post-processing Only special equipment can get the product, and the operation steps are cumbersome

The production method of N-n-butylthiophosphoric triamide reported in domestic patent literature [publication number CN1583767] also involves low-temperature reaction, and triethylamine is also used to absorb the hydrochloric acid produced in the production, which is unfavorable for the purification of the final product

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