CS266142B1

CS266142B1 - A method for preparing O.O-dimatyl-S-phthalimidomethyldithiophosphate

Info

Publication number: CS266142B1
Application number: CS878032A
Authority: CS
Inventors: Stefan Ing Csc Truchlik; Karol Ing Dulak
Original assignee: Truchlik Stefan; Dulak Karol
Priority date: 1987-11-09
Filing date: 1987-11-09
Publication date: 1989-11-14
Also published as: CS803287A1

Abstract

Riešenie sa týká spósobu přípravy 0,0- -dimetyl-S-ftalimidometylditiofosfátu reakciou suspenzie N-hydroxymetylftalimidu v inertnom organickom rozpúštadle s chlorovodíkom a/alebo vodným roztokom kyseliny chlorovodíkovej s následnou reakciou vzniknutého roztoku N-chlórmetylftalimidu so sodnou solou 0,0-dimetylditiofosforečnej kyseliny, čím sa získá roztok 0,0-dimetyl- -S-ftalimidometylditiofosfátu v inertnom organickom rozpúštadle, z ktorého po premytí s roztokom hydroxidu sodného a vody sa izoluje známým spósobom technický 0,0-dimetyl- -S-ftalimidometylditiofosfát vo vysokom výtažku a čistotě.The solution relates to a method of preparing 0,0-dimethyl-S-phthalimidomethyldithiophosphate by reacting a suspension of N-hydroxymethylphthalimide in an inert organic solvent with hydrogen chloride and/or an aqueous solution of hydrochloric acid followed by the reaction of the resulting N-chloromethylphthalimide solution with the sodium salt of 0,0-dimethyldithiophosphoric acid, thereby obtaining a solution of 0,0-dimethyl- -S-phthalimidomethyldithiophosphate in an inert organic solvent, from which, after washing with a solution of sodium hydroxide and water, technical 0,0-dimethyl- -S-phthalimidomethyldithiophosphate is isolated in a known manner in high yield and purity.

Description

2 CS 266 142 B1

The invention relates to a process for the preparation of 0,0-dimethyl-S-phthalimidomethyldithiophosphate (phosmet) from phthalimide as a starting material. Fosmet is the active ingredient of several insecticidal and acaricidal preparations. It is generally known that phosmet can be prepared by the reaction of N-halomethylphthalimide with alkali or alkali. ammonium salt of Ο, Ο-dimethyldithiophosphoric acid in the sense of the CO reaction.

.WHAT

wherein X is chlorine or bromine and Me is hydrogen, potassium or NH 4.

In the preparation of phosmet, N-bromomethylphthalimide (DE 930 446) and N-chloromethylphthalimide (US 2,767,194) are usually used as starting materials. Since the production of these starting materials follows the preparation of N-hydroxymethylphthalimide (DRP 104 624, Buc SR: J. Am. Chem. SOc. 69, 245 (1947), the possibility of simplifying the multistage synthesis of phosmet was sought. N-Hydroxymethylphthalimide with hydrogen chloride can be carried out in the presence of an inert solvent which will serve as the reaction medium in the next reaction step, and in another process for the production of phosmet (CS 162 692), anhydrous N-hydroxymethyl phthalimide suspended in toluene, The catalytic action of pyridine is first converted to N-chloromethylphthalimide by chloridyl chloride, which after crystallization is filtered off, washed with water and moist, added to the prepared toluene emulsion with water containing sodium Ο, Ο-dimethyldithiophosphoric acid, thereby achieving in the course of 1.5 h at 55-60 ° C, quench the reaction remove the impurities from the toluene layer (phthalimide, sulfur, etc.) by filtration, and after the toluene has been distilled off, the technical phthalate melt is obtained. The patent literature (SU 652 897, GB 1 487 038) describes a process wherein the starting N-hydroxymethylphthalimide in the form of a wet filter cake is suspended in benzene, reacted with 35-40% hydrochloric acid and hydrogen chloride to N-chloromethylphthalimide, which, in the form of a benzene solution with an aqueous solution of sodium Ο, ld-dimethyldithiophosphoric acid, gives a benzene solution of phosmet which, after washing with a 10% solution of sodium hydroxide and water, yields a technical phosmet after evaporation of the solvent. According to the aforementioned methods, the process according to CS 162 692 has the disadvantage that the starting material is anhydrous N-hydroxymethylphthalimide which, by reaction with thionyl chloride, yields N-chloromethyl-phthalamide which has to be filtered off, washed twice with cold water and used for reaction with sodium. Ο, Ο-dimethyldithiophosphoric acid salt in the presence of toluene and 0,0, S-trimethyldithiophosphate. After the reaction, the toluene layer is removed by further filtration to remove impurities and then the expected product is isolated. There is also no mention of how the technical product is de-0,0, S-trimethyldithiophosphate. The process uses thionyl chloride to produce N-chloromethylphthalimide, which is associated with the development of a mixture of sulfur dioxide and hydrogen chloride, which is either complicated to separate or oxidized to sulphate upon neutralization. Also, the handling of N-chloromethylphthalimide is extremely difficult.

The process whereby the starting feedstock is a wet N-hydroxymethyl-phthalimide filter cake (SU 652 897, GB 1 487 038), its preparation had to be avoided and the N-hydroxymethylphthalimide filtration from the formaldehyde-containing mother liquors was very unpleasant.

These drawbacks are overcome by the preparation of 0,0-dimethyl-S-phthalimidomethyldithiophosphate by reacting phthalimide with formaldehyde to remove excess formaldehyde, methanol and water by azeotropic distillation with an inert organic solvent, reaction of N-hydroxymethylphthalimide with hydrogen chloride followed by reaction of the resulting N-chloromethylphthalimide with the sodium salt of the 0,0-dimethyldithiophosphoric acid of the invention. SUMMARY OF THE INVENTION The present invention provides that the suspension of N-hydroxymethylphthalimide in an inert organic solvent is reacted with hydrogen chloride and / or aqueous hydrochloric acid at 20 ° C to 80 ° C and the resulting N-chloromethylphthalimide solution is reacted with sodium salt. Ο, Ο-dimethyldithiophosphoric acid at a temperature of 40 ° C to 70 ° C to form a solution of 0,0-dimethyl-S-phthalimidomethyldithiophosphate in an inert organic solvent from which, after washing with 0.5 to 8% sodium hydroxide solution high-purity high-purity, high purity technical O, O-dimethyl-S-phthalimidomethyldithiophosphate is isolated with water and, after removal of the solvent in a known manner. As the inert organic solvent, aromatic hydrocarbons such as benzene, toluene, xylene and mixtures thereof can be used, but 1,2-dichloroethane, carbon tetrachloride and the like can also be used. According to the present invention, high purity technical cosmetics containing more than 97% of O, O-dimethyl-S-phthalimidomethyl-dithiophosphate in more than 80% yield, calculated on the starting phthalimide, are extracted. Starting from anhydrous N-hydroxymethylphthalimide (CS 162 692), up to 95.2% yield of active compound calculated on hydroxymethylphthalamide is given. The product temperature of the product (69 ° C, 70 ° C) does not, however, correspond to the reported purity (98.5 i), since the pure cosmetic material is 74 ° C. When starting with a wet N-hydroxymethyl-phthalimide filter cake (SU 652 897, GB 1 487 038), a 73% yield of technical cosmetics is 95% pure. Advantages of the process according to the invention are as follows: N-hydroxymethylphthalimide is not required to be obtained in the form of a wet filter cake (CS 201 536) or in the form of a solid anhydrous product (CS 162 692). In the N-chloromethylphthalimide preparation step, it is not necessary to isolate and wash it separately (CS 162 692). Techn. phosmet, the reaction of a solution of N-chloromethylphthalimide with Ο, Ο-dimethyldithiophosphoric acid can also be carried out using the principle of a two-step excess of reactants (CS 253 920).

Despite the fact that the basic starting material is phthalimide, neither N-chloromethylphthalimide (CS 162 652) nor N-hydroxymethylphthalimide (SU 615 897GB 1 487 038) is isolated, but techn. phosmet in such a high purity that further crystallization is unnecessary.

These examples illustrate but do not limit the invention. EXAMPLE 1 101.2 parts of a 35.6% aqueous formaldehyde solution was added to 147.2 parts of phthalimide, and the mixture was heated to reflux for 1 hour after clarification of the reaction mixture.

Thereafter, a hot solution of N-hydroxymethylphthalimide was poured into 900 parts by volume of toluene and the resulting N-hydroxymethylphthalimide slurry was heated to reflux, while stirring and continuously separating the aqueous phase, the reaction mixture was heated until the reaction temperature reached 95 ° C. 68 parts by volume of an aqueous phase containing water, methanol and formaldehyde are obtained. After cooling the reaction mixture to 70 ° C, 348 parts of 32.4% hydrochloric acid were added. Then the temperature of the reaction mixture was adjusted to 34 ° C and 104 parts of hydrogen chloride was introduced into the mixture over 50 minutes. The reaction mixture was then slowly heated to 55 ° C to 60 ° C and maintained at this temperature for 1 hour while stirring, which was sufficient to sharpen the upper organic layer containing N-chloromethylphthalimide from the lower acid layer. To the separated 970 parts of a toluene solution of N-chloromethylphthalimide was added 439 parts of a 39.0% solution of sodium Ο, Ο-dimethyldithiophosphoric acid, the temperature of the reaction mixture was adjusted to 50 ° C to 55 ° C and at that temperature The reaction mixture was stirred vigorously for 3.5 h. Thereafter, the stirring was stopped, the lower aqueous salt-containing layer was separated, and the top toluene layer was washed with 400 parts by volume of 2% sodium hydroxide solution and 300 parts by cooling after cooling to 25 ° C to 30 ° C. water. The toluene layer was then removed from the solvent on a vacuum rotary evaporator, finally at a pressure of 2.6 kPa and a bath temperature of 80 ° C. 294.3 parts of the melt techn. a product which, upon solidification, crushing and drying under a stream of nitrogen, at 50 ° C, gave 264.9 parts of product with a 99.2% content of O, O-dimethyl-S-phthalimidomethyldithiophosphate, corresponding to an 82.81% yield; calcined phthalimide. Example 2 50.0 parts of a 36% aqueous formaldehyde solution were added to 73.6 parts of phthalimide and heated to reflux for 1 hour. The resulting solution of N-hydroxymethylphthalimide was then stirred into 400 parts by volume with stirring. the benzene and the azeotropic distillation mixture were freed of 32 parts by volume of the aqueous phase. Then, the mixture was cooled to 25 ° C, 240 parts of 41.5% hydrochloric acid was added to it and heated to 60 ° C for 1 hour and stirred for 1 hour at this temperature, the lower acid layer separated and the remaining 444, A portion of the benzene solution of N-chloromethylphthalimide was added with 227.0 parts of a 38.5% by weight solution of sodium O, O-dimethyldithiophosphoric acid and the mixture was then stirred at 50 ° C to 55 ° C for 3 hours. After the reaction mixture was cooled to 25 ° C, the lower aqueous layer was separated and the benzene solution was separated. Phosmet was washed with 200 parts by volume of 3% sodium hydroxide solution and 300 parts by volume of water. The washed solution was freed from the solvent by distillation on a vacuum rotary evaporator, under a stream of nitrogen, finally at a pressure of 1.3 kPa and a bath temperature of 80 ° C to obtain 130.5 parts of product containing 99.3% O-dimethyl after cooling and crystallization. -S-phthalimidomethyldithiophosphate corresponding to 81.7% yield calculated from phthalimide. Example 3 110.5 parts of a 32.6% formaldehyde solution were added to 147.2 parts of phthalimide, the mixture was heated to reflux for 1.5 hours, then 31 parts by volume of a mixture of water, formaldehyde and distilled water were distilled. methanol and a concentrated solution of N-hydroxymethylphthalimide savlial with stirring to 900 parts by volume of toluene and after heating to reflux, a further 40 parts of the aqueous phase are separated. Thereafter, the reaction mixture was cooled to 40 ° C, and 350 parts of a divided acidic layer was added therefrom to prepare a solution of N-chloromethyl-phthalimide from Experiment 1 which contained 32.6% hydrochloric acid at 40 ° C to 55 ° C. The reaction mixture was then heated to 60 ° C to 65 ° C and maintained at this temperature for 1 hour. The separation of the lower acid layer, from the N- toluene layer was followed by stirring at room temperature for 1 hour. chloromethyl-phthalimide, to which 462.0 parts of a 39.0% aqueous solution of sodium salt, O-dimethyldithiophosphoric acid, was added, the temperature of the reaction mixture was adjusted to 50 ° C to 55 ° C and the reaction mixture was stirred at this temperature. h. After the stirring was stopped, the bottom layer was separated with the excess of O, O-dimethyldithiophosphoric acid sodium salt from the toluene layer containing phosmet. The toluene layer was then washed with 400 parts of 2.5% sodium hydroxide solution and then with 400 parts of water. The toluene solution was then freed from the solvent by a vacuum rotary evaporator, finally at a pressure of 2.0 kPa and a bath temperature of 80 ° C to yield 288.5 g of melt containing 8% toluene and 91.4% 0.0-dimethyl- S-phthalimidomethyldithiophosphate, corresponding to a 83.05% yield calculated on phthalimide. The product can be used directly for the production of emulsion concentrates. Example 4

Of 147.2 parts of phthalimide, 110.5 parts of a 32.6% solution of formaldehyde, 900 parts by volume of toluene, 351 parts of the acid layer of Experiment 3, which contained 31.9% of hydrogen chloride and 106 liters of hydrogen chloride gas prepared by Example 3 toluene solution

Claims

5 N-chloromethylphthalimide to which a separate aqueous layer containing sodium Ο, Ο-dimethyldithiophosphoric acid from experiment 3 was added and stirring was stopped after 1 h of stirring at 50 ° C to 55 ° C, the aqueous layer was separated salt, which contained only 0.8 isodium salt of Ο, Ο-dimethyldithiophosphoric acid. To the toluene solution of 0,0-di-dimethyldithiophosphoric acid sodium salt, the temperature of the reaction mixture was adjusted to 50 ° C to 55 ° C and the reaction mixture was stirred for 3 hours at that temperature. techn. Phosmet with 500 parts of water. The washed toluene solution was then freed from the solvent on a vacuum rotary evaporator, finally at a pressure of 1.1 kPa, under a stream of nitrogen and a bath temperature of 80 ° C, yielding 262.7 parts of 99.3% product after cooling and solidification, corresponding to 82%. A 2% yield of the theoretical 317.3 parts. Example 5 103 parts of 35% formaldehyde solution were added to 147.2 parts of phthalimide, heated to reflux for 1 hour, then 32 parts of the aqueous phase were distilled off, 900 parts by volume of toluene was added and azeotropically all the water phase that distilled to the reaction mixture temperature of 95 ° C to 98 ° C was distilled off. The N-hydroxymethyl-phthalimide suspension was then cooled to 40 ° C, 350 parts of 32% hydrochloric acid were added thereto, and 109 parts of hydrogen chloride gas were introduced with stirring, and 60 ° C to 65 ° C was slowly heated. and after 1 h at this temperature, the lower acid layer was separated from the upper toluene layer containing N-chloromethylphthalimide. To the toluene layer was added 430.0 parts of a 39.8% aqueous solution of sodium os, dim-dimethyldithiophosphoric acid, the temperature of the mixture was adjusted to 50 ° C to 55 ° C and the reaction mixture was stirred for 3 hours. below 30 ° C, 23.8 parts of a 42% sodium hydroxide solution was added, and after brief mixing, the lower aqueous layer was separated from toluene, which was finally rinsed with 300 parts of water. The washed toluene layer was then freed from the solvent in a vacuum evaporator, finally at 2.7 kPa and a bath temperature of 75 ° C. 296.2 parts of melt techn. of the product to which 200 parts by volume of methanol was added and after dissolving and cooling to 7 ° C, 258.3 parts of crystalline 99.7% product was obtained, corresponding to a 81.2% yield calculated on phthalimide. EXAMPLE 6 A toluene solution of N-chloromethylphthalimide was prepared starting from the same amounts of raw materials and in the same manner as in Example 1 (instead of benzene only, using 216.2 parts of a 38.6% ammonium salt solution). the dimethyldithiophosphoric acid and the mixture was then stirred at 50 ° C to 55 ° C for 3 h. Subsequently, the bottom aqueous solution and the toluene solution were separated. The phosmet was washed with 200 parts by volume of a 5% solution of sodium hydroxide and then with 250 parts of water. The washed solution was freed from the solvent by distillation of a pressure of finally 1.5 kPa and a bath temperature of 80 ° C, yielding 131.6 parts of a product containing 99.2% of O, O-dimethyl-S-phthalimidomethyldithiophosphate after cooling and crystallization. A 3% yield calculated on the starting phthalimide. OBJECT OF THE INVENTION A process for preparing 0,0-dimethyl-S-phthalimidomethyldithiophosphate by reacting phthalimide with formaldehyde to remove excess formaldehyde, methanol and water by an azeotropic distillation with an inert organic solvent, reacting the resulting mixture containing N-hydroxymethyl-phthalimide with a hydrogen chloride followed by N- N- Ο, Ο-dimethyldithiophosphoric acid chloromethylphthalimide, characterized in that the suspension of N-hydroxymethyl-phthalimide in an inert organic solvent is reacted with hydrogen chloride and / or aqueous hydrochloric acid solution at 20 ° C to 80 ° C, leaving the resulting N-chloromethylphthalimide solution with Ο, Ο-dimethyldithiophosphoric acid sodium salt at 40 ° C to 70 ° C to form a Ο, Ο-dimethyl-S-phthalimidomethyldithiophosphate solution in an inert organic solvent from which, after washing with 0.5 to 8% sodium hydroxide solution and water and after removal of solvent i technical O, O-dimethyl-S-phthalimidomethyldithiophosphate is isolated.