KR810000912B1 - Process for the preparation of pure dialkyl phosphorochloridothionate - Google Patents

Abstract

Title compds. (I; R1,R2 = C1-12 alkyl-substituted group), useful intermediates for insecticide, plasticizer, rubbercuring agent, flame retardant, etc., were prepd. as follows. Bis(phosphorotioic)sulfide(II) or pirmary thioic acid(III; M1 = H, NH3, alkali earth metal, alkali metal) were chlorinated with chlorinating agent to give crude thionate compds., which were distilled and reacted with secondary thioic acid(IV; M2 = H, NH3, alkali earth metal, alkali metal) to give half-pure thionate compds. The obtained thionates were contacted with H2O to form org. and water phase compds. and then the org. phase was eliminated by distillation.

Description

Preparation of pure dialkyl phosphorochloridothionate

The present invention actually relates to a process for producing pure phosphorochloridothionate (hereafter referred to herein as "thiionate") in high yields.

The thionate made by the method of the present invention has the following general structural formula.

Wherein R ₁ and R ₂ are each alkyl substituents having 1-12 carbon atoms.

Thionates are valuable intermediates in the manufacture of pesticides, suspending agents, plasticizers, lubricant additives, rubber hardeners, flame retardants and many other useful chemicals.

Several methods have been used for the preparation and purification of thionates described above.

(1) US Patent No. 3,897,523 to Sorstokke

(2) US Pat. No. 3,794,703 to Beck et al.

(3) United States Patent No. 3,502,750 to Anglaret

(4) U.S. Patent No. 3,356,774 to Niermann et al.

(5) US Patent No. 3,098,866 to Divine

(6) US Pat. No. 3,089,800 to Chupp et al.

(7) US Patent No. 2,900,406 to Vogel et al.

(8) US Pat. No. 2,715,136 to Toy et al.

(9) US Patent No. 2,692,893 to Hechenbleikner

(10) US Patent No. 2,482,063 to Hechenbleikner

(11) Hechenbleikner, British Patent No. 646,188

(12) British Patent No. 1,289,396 to Hercules, Inc.

(13) German Patent No. 1,801,432 to Knapsack, Ag

That is it.

All references mentioned above are incorporated here by reference.

In general, various commercial thionates are obtained by chlorination of the initial reactant with a chlorinating agent, which has a general structural formula when m is an integer (particularly 2).

General formula when the phosphorus bis (phosphothioic) sulfide or M is hydrogen, ammonium, alkaline earth metal or alkali metal

At least one of the compounds having thio acids or salts thereof should be included.

In the chlorination step, a crude thionate reaction mixture is formed comprising thionate and impurities, which is usually purified. Chlorinating agents used include chlorine, dichloride, monochloride, sulfuryl chloride and phosphorus pentachloride.

The process for the preparation of thionates by chlorination of bis (phosphothioic) sulfides is described, for example, in more detail in previously mentioned US Pat. No. 2,482,063 to Hekenblickner.

Methods for preparing thionates by chlorinating thioacids or salts thereof are described in more detail in previously mentioned US Pat. Nos. 2,692,893 and UK 646,188.

인 그룹일 때 다음과 같다.As noted earlier, the above-mentioned manufacturing process produces by-product impurities. Impurities that are by-products in the description of the recipe used to prepare the thionate are as defined above for M and X is

When the group is as follows.

For example, in a typical form of the (K) reaction, bis (0,0-diethyl phosphorothioic) disulfide reacts with chlorine to produce 0,0-diethylchlorothiophosphate as follows.

In this reaction, sulfur monochloride is produced as a byproduct of impurities.

(1) In a typical form of the reaction, 0,0-diethyldithiophosphoric acid reacts with chlorine to produce 0,0-diethylchlorothiophosphate as follows.

This reaction produces sulfur monochloride and hydrochloric acid as byproducts. If thionate is produced in a two-stage reaction, additional impurities may be produced.

Representative two-step reactions include reacting an alcohol with a phosphorus sulfide compound to produce a crude thioacid.

Here, for example, R is an alkyl substituent having 1-12 carbon atoms. Crude acid reaction mixtures are difficult to purify. It is commonly used as an initial reactant to direct chlorination to produce a wonthionate reaction mixture.

The crude zionate reaction mixture made from this two-step reaction not only has impurities, which are by-products produced in the chlorination step, but also contains hydrogen sulfide, unreacted alcohol, or chlorinated products therefrom. Thus, as shown above, the zionionate reaction mixture contains MCl, S ₂ Cl ₂ , S, SO ₂ , (X) ₂ S ₂ , the chlorinated product of H ₂ S, H ₂ S that did not react with alcohol, It may also contain a large amount of impurities, such as by-products such as unreacted alcohol, unreacted XSM, and unreacted chlorinating agent, which must be separated. The actual part of the impurity in the joionate reaction mixture is usually sulfur monochloride.

In addition, there are many side reaction impurities formed by varying the conditions of the reaction and the reactants, i.e. the chlorinated bis (phosphothioic) sulfides or thio acids or salts thereof, as well as the amount due to the form of the chlorinating agent. It makes the wonthionate reaction mixture even more impure.

For example, the zionionate reaction mixture may become even more impure with side reaction impurities that satisfy the following structural formula when n is 0 or 1 and R is R ₁ or R ₂ .

For example, these side reaction impurities may be filled when the remaining atoms are filled by R ₁ and R ₂ or one of them.

It may include one or more compounds having a.

The need to improve the quality of the zionate reaction mixture is readily apparent in the following reactions using the same and the products derived therefrom.

Indeed, unless pure thionate is used, the effectiveness of the method used to prepare the derivatives is in fact reduced. For example, impurities that can be obtained in actual amounts from chlorination

(The remaining atoms are filled with R ₁ or R ₂ here.)

그룹을 포함한다.It contains twice as many active groups (ie chlorine substituents) as desired thionates. In addition, these impurities react with products that do not have the desired properties of the corresponding thionate derivatives.

Include a group.

Many attempts have been made to remove impurities from the jothionate reaction mixture to produce purer thionate products, for example:

[Solvent extraction method]

Extraction of the jothionate reaction mixture with an organic solvent has been used to remove impurities. The present invention is unsatisfactory for commercial reasons due to the similar solubility properties of thionate and related impurities. Satisfactory separation of the desired thionate product from impurities by this technique requires various extractions resulting in loss of thionate.

[Water contact / hydrolysis]

Separation of sulfur monochloride from either the crude zionate reaction mixture or the distilled crude zionate reaction mixture can be accomplished by hydrolysis. Hydrolysis can be carried out by slowly mixing the zionate reaction mixture with water. Sulfur monochloride is hydrolyzed to aqueous acids-hydrochloric or thiosulfate-and other products.

However, hydrolysis of sulfur monochloride in the thionate reaction mixture produces free sulfur. The sulfur may have many forms of crystals, clad particles, or semisolid plastics of syrup. In particular, in commercial processes such materials create significant difficulties in the separation and recovery of organic layers comprising thionate.

In addition, the water contact / hydrolysis method does not actually remove all impurities, including all sulfur monochloride.

[distillation]

Removal of impurities, including phosphorus and non-sulfur, has been attempted by fractional distillation. This method is unsatisfactory commercially because the boiling point of impurities and thionate is very close. Full separation of thionate from impurities by distillation is impossible unless continued several times. The yield of thionate can be reduced because the reaction of thionate and sulfur monochloride when distilled at high temperature. In addition, distillation at elevated temperatures can cause other side reactions, which can lead to the formation of sulfur that contaminates the distillation apparatus.

[Tioic acid treatment method]

Another method for purifying the jothionate reaction mixture is to mix and react the dialkyl phosphoric dithio acid with the jothionate reaction mixture to react with some impurities to form additional thionate.

This method is not completely satisfactory because the reactants contain the actual amount of impurities that do not react with the thio acid. Moreover, the yield of thionate based on the total amount of thio acid becomes small. This is because thio acid which is not converted to thionate is not recovered. This treatment is described in detail in the above-mentioned Beck literature.

None of the aforementioned methods of treating the zionate reaction mixture and its known combinations are actually completely satisfactory for producing high yields of pure thionate.

It is therefore an object of the present invention to provide a process for obtaining high yields of pure thionate in practice. Still other objects and advantages of the present invention will become apparent to those skilled in the art from the following publication.

The process of the present invention comprises (1) an initial composition containing at least one compound selected from the group consisting of bis (phosphothioic) sulfide of formula (II) and primary thio acid or salt thereof of formula (III) Chlorination of the reaction composition with a chlorinating agent produces a crude thionate reaction mixture containing thionate and impurities, and (2) distillation of the crude thionate reaction mixture to contain thionate and a small amount of impurities. Produces an initial thionate effluent, and (3) produces a semi-pure thionate reaction mixture by mixing and reacting a secondary thio acid or a salt thereof with the initial thionate effluent. (4) contacting the semi-pure thionate reaction mixture with water to form an organic phase and an aqueous phase, and (5) distilling the organic phase to obtain the most substantially pure thionate. The thio-alkyl phosphorothioate claw with the carbonate to made by the process of step 5, the structural formula (I) to produce a distillate Lido relates to a process of the thiocyanate.

Wherein R ₁ and R ₂ are each alkyl substituents having from 1 to 12 carbon atoms.

Wherein M ₁ is selected from the group consisting of hydrogen, ammonium, alkaline earth metals and alkali metals.

Wherein M ₂ is selected from the group consisting of hydrogen, ammonium, alkaline earth metals and alkali metals.

Unexpectedly, in this process, no sulfur precipitation occurs during the contacting step (4). Rather, the process further goes to recycling the residual fraction as part or all of the initial reactant and repeating at least steps 1) and 2) chlorination of the initial reactant and distillation of the crude reaction mixture resulting therefrom. It will include.

Furthermore, the process consisting of recirculating the resid fraction for use as all or part of the initial reactants and actually repeating the reaction steps 1) to 5) to obtain the final thionate effluent in pure thionate yield is particularly preferred. .

This is especially better for processes carried out in continuous processes. The term “yield” or “percent yield” used here is based on the theory of thionate produced when bis (phosphothioic) sulfide or both primary and secondary thio acids are converted to thionates. The fraction or percentage of the actual amount of thionate to be produced.

The term " alkyl substituent " means a monovalent radical derived by removing one hydrogen atom from a saturated or straight chain branched hydrocarbon having the general formula CnH ₂ n ₊₁ when n is an integer.

The term "ammonium" means -NH ₄ which is a monovalent group, and "alkaline earth metal" means magnesium, calcium, strontium, barium, or radium elements.

In addition, "alkali metal" means lithium, sodium, potassium, rubidium, cesium, francium element, of which sodium and potassium are particularly preferred.

As pointed out earlier, the chlorinating agents are chlorine, sulfur dichloride, sulfur monochloride, sulfuryl chloride, phosphorus pentachloride, of which chlorine is particularly good. R ₁ and R ₂ are the same alkyl substituents, with the same alkyl substituent having 1 to 8 carbon atoms each.

Thioic acid and its salts are the same as secondary thioacids and their salts, especially when both M ₁ and M ₂ are oxygen, ie both primary and secondary thio acids are equal. The molar ratio of the amount of secondary thio acid and salt thereof relative to the amount of impurities in the initial thionate effluent is taken not to be greater than at least approximately 0.5: 1, preferably about 2: 1. Especially when the molar ratio is about 1: 1.

It was found that when the molar ratio was less than about 0.5: 1, precipitation of sulfur occurred in the contacting step 4).

In addition, when the molar ratio is greater than about 2: 1, the present invention is effective but economically impractical and unnecessary.

As noted earlier, sulfur monochloride actually accounts for some of the total impurity in the jothionate reaction mixture and is transported to the initial thionate effluent to determine the amount of secondary thioacid and its salts relative to the amount of sulfur monochloride impurities in the initial thionate effluent. The amount ratio is at least approximately 0.5: 1, in particular no greater than about 2: 1. It is especially good when the molar ratio is about 1: 1.

Particularly preferred embodiments of the invention comprise (1) an initial containing at least one compound selected from the group consisting of bis (phosphothioic) sulfides of formula (II) and thio acids of formula (III) Chlorination of the reaction composition with chlorine yields a crude reaction mixture containing thionate and sulfur monochloride, and (2) an initial reaction containing thionate and sulfur monochloride by distillation of the crude reaction mixture. To produce a semi pure thionate reaction mixture by (3) mixing and reacting at least a sufficient amount of thio acid with the initial thionate effluent to react with at least a portion of sulfur monochloride. (4) contacting the semipure thionate reaction mixture with water to form an organic phase and an aqueous phase, and (5) distilling the organic phase to substantially pure To produce the final thionate effluent of the onate, (6) recycle the residual fraction for use as the initial reaction composition, and at least repeat the steps (1) and (2) Production of substantially pure thionate in yield.

Wherein R ₃ is an alkyl substituent having from 1 to 8 carbon atoms.

It is also particularly good to further go through the steps 3) to 5) in order to obtain a high yield of actually pure thionate final thionate effluent. It is also better when the process is continuous.

The molar ratio of the amount of thio acid reacted with the initial thionate effluent with respect to the amount of sulfur monochloride contained therein is preferably at least about 0.5: 1 and not more than about 2: 1. Especially good is a molar ratio of about 1: 1.

The process of the present invention is particularly suitable for producing high yields of substantially pure dimethyl and diethylphosphorochloridothionate. In particular, the chlorination of the initial reactants is accomplished by methods well known in the art, for example described in the aforementioned Hekenblinder literature.

Suitable sulfur-free organic solvents can be used in the present process. Such solvents include carbon tetrachloride, chloroform, benzene, toluene, xylene, chlorobenzene, tetrachloroethane, methylene chloride, ethylene dichloride. However, no solvent should be used during chlorination.

The chlorination is preferably performed within the temperature range of approximately 0 ° C to 80 ° C. However, temperatures outside this range may be used depending on the type of reactant used. Cooling means may be necessary because the reaction is somewhat exothermic, especially in the early stages.

Indeed it was unexpectedly found that low chlorination temperatures, i.e. temperatures of about 40 ° C. or below, may be used without the precipitation of sulfur during the contacting step 4) while maintaining a high yield of pure thionate product. Distillation of the zionionate reaction mixture (step 2) and organic phase (step 5) is by any method known in the art. This distillation is generally carried out under reduced pressure.

Distillation of the jothonate reaction mixture separates the impurities from the reaction mixture of the jothonate to make an initial thionate effluent containing thionate and a small amount of impurities. As noted earlier, the actual part of the impurities in the initial thionate effluent is sulfur monochloride. The residue after distillation consists of impurities boiling at higher temperatures.

The distillation of the organic phase obtained by contacting the semi-pure thionate reaction mixture with water separates the impurities and water from the thionate to actually produce the final effluent of the pure thionate. Residue fractions containing impurities with boiling points can be recycled to the chlorination step 1). The actual part of the residue will be the bis (phosphothioic) sulfide of (2).

In particular, the jothionate reaction mixture or organic phase is a low boiling material which exhibits the characteristics of a particular chlorination reaction (step 1) or mixing and reaction), i.e. hydrogen chloride, hydrogen sulfide, sulfur dioxide, which is boiling below the boiling point of the desired thionate. Distilled to remove alkyl chlorides, inert organic solvents, and the like. The thionate effluent is then obtained by distilling the others under reduced pressure.

Distillation may also be carried out with a wiped film evaporator, in which a large part of the evaporator containing thionate is formed and separated from the remnant fraction containing the relatively inert material. The evaporator-rich fraction is released from the evaporator to the cooler. The residue is discharged from the evaporator as a liquid.

Residue in the distillation stage of the distillation step 5) can be transferred to a by-product recovery device, for example, in which the residue material can be converted into a useful product such as phosphoric acid or sulfur.

Optionally, the residual fraction in the distillation step 5) can be recycled for use as an initial reactant for chlorination where bis (phosphothioic) sulfides and thio acids or either are converted to thionates. It may be.

The distillation of the jothionate reaction mixture gives the initial thionate effluent, which is then mixed and reacted with thio acid and its salt (step 3).

Mixing and reacting the initial thionate effluent with the amount of thio acid and its salt can be accomplished by adding the initial thionate effluent and mixing for at least one minute at a temperature of about 10 ° C. to about 80 ° C. have.

It is of great importance that the alkyl substituents of the secondary thio acids and their salts should be consistent with the alkyl substituents of the thionate made. Thus, for example, if the process is used to produce dimethylphosphorochloridionate, then dimethylphosphorodithioic acid or a salt thereof is used. Similarly, if the process is intended to produce diethyl phosphorochloridothionate, diethylphosphorodithioic acid or a salt thereof is used.

A sufficient amount of thio acid or its salt is added to react with at least some impurities in the initial thionate distillate to produce a semipure thionate reaction mixture.

Unexpectedly, it has been found that by contacting a semi-pure thionate reaction mixture with water, the sulfur deposits ritually involved in such contact are removed.

In general, the secondary thioacid and its salts may be added to the initial thionate effluent such that the molar ratio of the impurity amount in the initial thionate effluent is at least 0.5: 1 and more than 2: 1. It is especially preferable that the molar ratio is approximately 1: 1.

The amount and type of impurities in the initial thionate effluent is a well known technique for this technique, namely the KI method for determining sulfur monochloride (for example, some sulfur compounds on pages 17-22 of the Indian Academy of Science pictorials in 1953). Can be easily determined. It has been found that sulfur monochloride is a major component of the impurities contained in the initial thionate effluent. The amount of sulfur monochloride can be used to determine the amount of secondary thio acid or salt thereof required. The molar ratio of thioacid or its salt to sulfur monochloride in the initial thionate effluent should be at least 0.5: 1 and rather not more than 2: 1. Especially better is a molar ratio of 1: 1.

In general, the time to mix thio acid and its salt with the initial thionate effluent depends on several factors: the size of the batch, the mixing process, the impurities, the temperature and the like. However, it is known that about 1 minute to 1 hour is sufficient for thio acid and its salt to react with at least some impurities.

The addition of thio acid or its salt to the initial thionate effluent occurs at approximately 10 ° C. to 80 ° C. However, from about 20 to 45 ℃ is good.

The reaction of thio acid or its salt with the initial thionate effluent yields a semi pure thionate reaction mixture which is then contacted with water in step 4).

Contacting the semi-pure thionate reaction mixture with water is both a hydrolysis process and a liquid-liquid extraction process. The contacting step includes contacting the water and the semi-pure reaction mixture and separating the organic and water phases therefrom. The temperature in contact with water can vary widely from 5 ° C. to 75 ° C., but is preferably in the range of approximately 10 ° C. to 50 ° C. The time of contact and the amount of water to be used also include the amount of impurities, the quality or degree of improvement desired, the equipment available, the contact rate or type of contact (e.g., simply shaking, boiling water into the composition, Depending on the same or opposite flow, mechanical stirring, contact temperature, etc. In other words, the time or period of contact between water and the semi-pure thionate reaction mixture and the amount of water used are indicated by the manufacturer's design. In general, the contact time should be as short as necessary to achieve the desired improvement, and the amount of water used will range from 0.1 to 10 for each volume of the semi-pure thionate reaction mixture.

In the one-stage contact process, the volume of water for each volume of the semi-pure thionate reaction mixture consists of a satisfactory ratio of about 0.25 to 2.5.

When some of the impurities are water soluble, water forms a water phase and thionate is included in the organic phase. These two phases are separated but the aqueous phase is transferred to, for example, a by-product recovery system. The organic phase is then distilled off (step 5). Distillation of the organic phase is accomplished by methods well known in the art as described above.

It is particularly good to recycle the residual fraction from the distillation step 5) to be used as an initial reactant in the distillation step at least subsequent to the chlorination step in order to produce a high yield of actually pure thionate. The effluent from the distillation stage enters the mixing reaction stage, the contacting stage and the distillation stage.

The initial reactants used in the chlorination step consist not only of the resid fraction recycled from step 5) but may also consist of an additional amount of bis (phosphothioic) sulfidenathioic acid or salts thereof.

In a continuous process, the residual fraction from the distillation step of step 5) can be continuously recycled to use as a starting reactant and an additional amount of bis (phosphothioic) sulfide or thio acid or salt thereof can be added thereto. As noted earlier, the addition of secondary thioacid or its salts to the initial thionate distillate not only increases the final yield of the thionate when the resid fraction is recycled, but also removes the precipitation of sulfur, which is typically associated with water contact / hydrolysis treatment. Was unexpectedly discovered.

Furthermore, the process of the present invention is that all or part of the chlorination step can be completed at a low temperature, i.e. 40 ° C and below, without the precipitation of sulfur in contacting step 4) and without reducing the purity or reducing the yield. This is an improvement over the prior art process.

Low temperatures are advantageous for reducing sulfur precipitation during the formation of sulfur monochloride and chlorination, but disadvantageous for the formation of other byproducts, impurities.

Chlorination (and thus an increased amount of sulfur monochloride) at low temperatures combined only with thioacid treatment requires the use of large amounts of thio acid to react with sulfur monochloride. It is essential that such large amounts of thio acids be consumed without recycling the reacted or unreacted thio acids. In combination with only water contact / hydrolysis treatment methods, chlorination at low temperatures results in large amounts of sulfur precipitation due to the reaction of water with sulfur monochloride.

Surprisingly and unexpectedly, bis (phosphothioic) liquor, which reacts by mixing thio acid or its salt with an initial thionate effluent, allows sulfur monochloride impurities to contact water and recycle to chlorinated to the desired thionate without causing sulfur precipitation. The transition to feed is made.

Thus, as described above, the process of the present invention is particularly advantageous over prior art processes in that thionate yield and purity increase under more favorable process reaction conditions.

The following are examples of processes that are good for describing the invention and its advantages more clearly, but do not limit the scope thereof.

Example 1

[Dimethyl phosphorochloridothionate]

Fill a 500 milliliter flask with 158 grams (1 mole) of dimethyl phosphorodithioic acid. The thioic acid is heated to 60 ° C. and 77 grams (1.08 mole) of chlorine is added to bubbling for 2 hours bubbling in the mixture to form a crude zionate reaction mixture.

The crude reaction mixture is distilled on a wipe film evaporator with a surface temperature of 90-95 ° C. under 5 mm Hg vacuum. The initial thionate effluent (135.7 grams) was analyzed by KI titration method and found to contain 6.9% (0.070 mol) of sulfur monochloride.

To 134 grams of the stirred initial thionate effluent was slowly added 13.0 grams of dimethyl phosphorodithioic acid (0.082 mol) while maintaining a temperature of 45 ° C. The resulting rather pure thionate reaction mixture is stirred for 15 minutes and then slowly added while shaking in 105 milliliters of distilled water. The organic layer is separated and distilled to form the final thionate effluent.

102.1 grams of the effluent are analyzed to find that chlorinated thionate contains dimethylphospho higher than 99%. 19.5 grams of residue oil is brown oil.

A 500 milliliter flask is then charged with 158 grams (1 mole) of dimethyl phosphorodithioic acid and 16.2 grams of brown residue. 81.3 grams (1.14 moles) of chlorine is added to the solution while stirring at 60 ° C.-65 ° C. to bubbling in the solution for 2 hours to form the jothonate reaction mixture. This jothonate reaction mixture is distilled to produce 144 grams of initial thionate effluent containing 6.2% S ₂ Cl ₂ (0.064 moles). To this 141.5 grams of this effluent is added 12.0 grams (0.76 moles) of dimethyl phosphorodithioic acid. The resulting mixture is hydrolyzed with 120 grams of water and redistilled. An analysis of 113.0 grams of the final thionate effluent reveals higher than 99% dimethyl phosphorochloridothionate. 16.7 grams of residue are left to recycle.

Example 2

[Diethyl Phosphorochloridionate]

186 grams (1 mole) of diethyl phosphorodithioic acid is placed in a 500 milliliter flask. The thioic acid is heated to 60 ° C. and 77 grams (1.08 mole) of chlorine is added to cause the mixture to bubbling for 2 hours to form a crude reaction mixture.

The crude thionate reaction mixture was distilled as in Example 1 to yield 161.6 grams of the initial thionate effluent containing diethyl phosphorochloridothionate which was not pure. 9.5 grams of diethyl phosphorodithioic acid (0.051 mol) is added to 159 grams of the effluent, which is stirred under a careful temperature. The resulting mixture is slowly added to 126 grams of water.

After separating the two phases, the organic phase is distilled to obtain 138.0 grams of higher than 99% pure diethyl phosphorochloridothionate. The residue fraction is 13.1 grams of brown oil.

Another 186 grams of diethyl phosphorodithioic acid is added to 11.4 grams of residue and the mixture is chlorinated with 81 grams (1.41 mole) of chlorine as above. This is distilled off to obtain 170.8 grams of the initial thionate effluent. This effluent will contain 2.1% S ₂ Cl ₂ (0.027 moles). Next, 9.9 grams of diethyl phosphorodithioic acid (0.053 mol) is added, washed with water and distilled to obtain 145.5 grams of diethyl phosphorochloridothionate having a purity of 99% and 13.1 grams of recyclable residue. The overall yield based on chlorinated thio acid is 74.4%.

Example 3

[Dimethyl Phosphorochloridothionate (DMPCT) -Washing of Sulfur Monochloride]

Three DMPCT solutions containing 10% of the weight of S ₂ Cl ₂ are prepared. One solution (solution 1) is washed with water, distilled and no further treatment. The other two solutions (solutions 2 and 3) are treated with dimethyl phosphorodithioic acid (DMPTA) as described in Example 1. The results shown in the table below demonstrate that the DMPTC obtained in the treated example is increased and sulfur precipitation is removed in the water contacting step.

TABLE 1

Example 4

[Dimethyl phosphorochloridothionate]

158 grams (1 mole) of dimethyl phosphorodithioic acid is placed in a 500 ml flask. Heat the thio acid to 60 ° C and add 56 grams (0.788 mole) of chlorine to bubble bubbling for 1.5 hours to form a reaction mixture, cool to 35 ° C. and add another 26 grams (0.366 mole) of chlorine to 0.5 The temporal mixture is bubbled up to give the jothionate reaction mixture.

The zionionate reaction mixture is distilled through a wiped film evaporator at a surface temperature of 90-95 ° C. under 5 milliliters Hg vacuum. The initial thionate effluent obtained is 162.8 grams, and it is analyzed by KI titration method to find that the sulfur monochloride weight contains 11.5% (0.14 mol). Stir 160 grams of initial thionate effluent and slowly add 25 grams of dimethyl phosphorodithioic acid (0.16 mole) while maintaining the temperature below 45 ° C. The resulting semi-pure thionate reaction mixture is stirred for 15 minutes and then slowly added while shaking in 150 milliliters of distilled water. The organic layer is separated and distilled to form the final thionate effluent.

Analysis of 114.1 grams of the effluent reveals more than 99% of dimethyl phosphorochloridothionate. At this time, 41.8 grams of residual oil is brown oil. Next, add 158 grams (1 mole) of thio acid and 38 grams of brown residue to a 500 milliliter flask. While stirring the solution at 60-65 ° C, 58 grams (0.816 mole) of chlorine was added to bubbling bubbles in the solution for 1.5 hours to form a reaction mixture and the mixture was cooled to 35 ° C. to 30.7 grams (0.432 mole). Chlorine) is added to bubbling bubbling in the solution for 0.5 hours to form the jothonate reaction mixture. This jothonate reaction mixture is distilled off to give 179.5 grams of an initial thionate effluent containing 11.6% (0.16 mole) S ₂ Cl ₂ . To 178 grams of this effluent is added 29 grams (0.18 mole) of dimethyl phosphorodithioic acid. The resulting mixture is hydrolyzed and distilled with 150 grams of water. Analysis of 121 grams of the final thionate effluent reveals that 99% or more of dimethyl phosphorochloridothionate is included. Residue is 53.8 grams, but preserved for further recycling.

Claims (1)

As described above in the text, (1) at least one compound selected from the group consisting of bis (phosphothioic) sulfide of formula (II) and primary thio acid or salt thereof of formula (III) By chlorination of the initial reaction composition containing with a chlorinating agent, a crude thionate reaction mixture containing thionate and impurities is produced, and (2) the above zionionate reaction mixture is distilled off to obtain a thionate and a small amount of the reaction mixture. A crude thionate effluent containing an impurity is produced, and (3) a semi pure thionate reaction by mixing and reacting a secondary thio acid or salt thereof with the initial thionate effluent. Forming a mixture, (4) forming an organic phase and an aqueous phase by contacting the semipure thionate reaction mixture with water, and (5) substantially pure by distilling the organic phase. O di-alkyl phosphorothioate claw Lido preparation of thiocyanate with a final thiocyanate made to a 5-step process that generates the effluent of carbonate structural formula (I).

Wherein R ₁ and R ₂ are each alkyl substituents having from 1 to 12 carbon atoms.

Wherein M ₁ is selected from the group consisting of hydrogen, ammonium, alkaline earth metals and alkali metals.

Wherein M ₂ is selected from the group consisting of hydrogen, ammonium, alkaline earth metals and alkali metals.