DE2713049A1 - METHOD FOR PRODUCING TRIORGANOZIN HALOGENIDES - Google Patents

Description

Process for the production of

Triorganotin halides The invention relates to a Process for the production of organotin halides, in particular tricyclohexyltin halides.

Tricyclohexyl tin chloride can be prepared by reacting a Cyclohexyl Grignard compound and tin (IV) chloride in a molar ratio of 3: 1 Addition of the tin (IV) chloride to the Grignard compound gives a low yield of tricyclohexyltin chloride with a large proportion of tetracyclohexyltin. the reverse procedure, namely the addition of the Grignard compound to the tin (IV> chloride is also known from GB-PS 1084076 and gives tricyclohexyltin chloride. In particular if the Grignard compound and part of the tin (IV) chloride is added simultaneously to the remaining tin (IV) chloride and then the The remainder of the Grignard compound is added according to the information in the prior publication obtained an 87% yield of tricyclohexyltin chloride.

A reverse addition procedure has now been found that is simpler than the latter method and a good yield of the desired tricyclohexyltin halides (and their ring-alkylated products) and the corresponding obtained therefrom Hydroxides.

According to one embodiment, the invention provides a method created for the production of triorganotin halides, a cycloalkylmagnesium halide Grignard compound, in which the cycloalkyl group is a cyclohexyl group or an alkyl-cyclohexyl group is, in which there are 1 - 3 alkyl groups with 1 - 4 carbon atoms each and in which the halide is a chloride, bromide or iodide, to a tin (IV) halide, in which the halide is a chloride, bromide or iodide, in a molar ratio of 3 + 0.3: 1 is added and the cycloalkyl magnesium halide in an ether is dissolved as a solvent and the tin (IV) halide in one inert liquid diluent is present, which is characterized in that the tin (IV) halide with respect to the diluent in an amount by weight of less than 25 wt.% Is present and that the addition is carried out with stirring, wherein a reaction mixture containing a tricycloalkyltin halide is obtained. Preferably, the reaction mixture is left for at least 5 minutes after the addition is complete kept under conditions under which the reaction will proceed, e.g. at a temperature of at least 400C, e.g. from 40-1500C, in particular from 90-1500C.

The concentration of the Grignard compound in the ether can continue within Ranges vary, but the tin (IV) halide is in one concentration of less than 25% by weight of the diluent (i.e., percentage by weight Tin (IV) halide to diluent), e.g. in an amount of 5 - 25% by weight, such as 9-15% by weight or 10-25% by weight, e.g. 10-20% by weight and in particular 15-20 % By weight or 15-25% by weight. The Grignard compound is usually in one concentration of 15 - 80% by weight in the ether (i.e. the percentage by weight of the Grignard compound to ether) e.g. in an amount of 40-80% by weight, such as 40-70% by weight, preferably 50-65% by weight and in particular 53-60% by weight.

The cycloalkyl group in the cycloalkyl magnesium halide Grignard compound may be a cyclohexyl group or an alkylcyclohexyl group having 1 or 2 alkyl groups be in the ring of 1 or 2 carbon atoms each. While the cycloalkyl group is preferably a cyclohexyl group, other examples are methyl and ethyl-cyclohexyl groups. Preferably the halide is in the cycloalkyl magnesium halide and the tin (IV) halide the same and preferably the chloride.

The Grignard compound is made from the corresponding cycloalkyl halide made with magnesium in the usual way. The reaction can optionally go through Addition of iodine, an iodide and in the case of cycloalkyl chlorides be started with a little of the corresponding cycloalkyl bromide. The reaction will usually carried out in an ether as a solvent, such as diethyl ether or Tetrahydrofuran. Preferably the ether used as the solvent is the same than that used in the method of the invention.

Therefore, the Grignard compound is preferably used in the ethereal Solution prepared, the solution filtered to remove any unreacted magnesium or to remove other insoluble components and is then ready for use in the method according to the invention. The creation of the Grignard connection, its subsequent Handling and reaction with the tin (IV) halide are all preferred carried out in the absence of moisture, e.g. by having an inert atmosphere is maintained by e.g. nitrogen gas.

The ether used as solvent C. for the Grignard compound is preferably one of the formula R1 - (OR3) n -OR2 in which either R1 and R2, which can be the same or different, but are preferably the same, are alkyl groups of 1 - 6 carbon atoms and R3 is an alkylene group with 1 - 4 carbon atoms, is usually 2 or 3 carbon atoms and n = 0 or 1 or when n = 0 is, R1 and R2 together form a divalent radical of 4 or 5 chain links, which is a divalent saturated or ethylenically unsaturated aliphatic group, usually represents an aliphatic hydrocarbon group in which the chain from carbon atoms, optionally through an oxygen atom or subnoci? -an -NR4 group / in which R4 is an alkyl group with 1 - 4 carbon atoms means. Thus, the ether can, if n = O, a simple dialkyl ether with 1 - 6 carbon atoms, or it can, if n = 1, be a glycol diether, in which R3 is an ethylene radical, or it can, if n = 0, a cyclic Be ether with 5 or 6 ring atoms, in which R1 and R2 together form a divalent Form a group. Examples of such dialkyl ethers are diethyl, dipropyl, diisopropyl, Di-n-butyl, di-n- and isoamyl ethers and di-n-hexyl ether. Examples of glycol diets are ethylene glycol dimethyl, diethyl and di-n-butyl ether.

Examples of cyclic ethers are tetrahydrofuran, 2-methyltetrahydrofuran, 2-methoxy- and 2-ethoxy-methyltetrahydrofuran, tetrahydropyran, 2-methoxy- and 2-thoxy-tetrahydropyran, N-methylmorpholine and dioxane. The ether preferably has a total of 4 to 8 carbon atoms and 1 or 2 oxygen atoms. Examples of such ethers are diethyl, diisopropyl, Dipropyl and dibutyl ethers, the dimethyl and diethyl ethers of ethylene glycol, dioxane and tetrahydrofuran, which is most preferred. The ether preferably has a boiling point under reaction pressure of usually below atmospheric pressure 105 0C and especially less than 900C, e.g. 35 - 900C.

The liquid inert diluent in which the tin (IV) halide is usually a solvent for the stannous halide and usually a hydrocarbon.

Examples of diluents are aliphatic hydrocarbons, E.g. petroleum ether with boiling points in the range of 60 - 1400C, especially 100 - 1200C and 120 - 1400C, cycloaliphatic hydrocarbons, e.g. cyclohexane, aromatic hydrocarbons such as benzene and alkylbenzenes such as toluene and xylene. The inert diluent preferably has a boiling point below the reaction pressure of at least 1050C. Examples of such preferred diluents are toluene and xylene. Xylene is most preferred.

The Grignard compound in the ether solution is added to one stirred mixture of the diluent and the tin (IV) halide. In contrast according to the known method, the Grignard compound becomes the total amount of the halide added and no tin (IV) halide is added simultaneously with that of the Grignard compound admitted. In addition, there is no subsequent separate addition of additional Diluent before after the reaction has started. In the Encore the Grignard compound is added to the tin (IV) chloride to form a Reaction mixture which is tin (IV) chloride and an initial reaction product contains, and then further Grignard compound is added to this reaction mixture, until all of the Grignard compound has been added. The total mole of the Grignard compound added to the tin (IV) chloride is 2.7: 1 to 3.3: 1, e.g. 2.7: 1 to 2.95: 1, but preferably 2.8 1 to 3.05: 1, e.g. 2.9: 1 to 3.05: 1, in particular about the stoichiometric value 3: 1.

As the reaction proceeds, the reaction mixture becomes more viscous. In the known reverse addition method, the amount of diluent was namely xylene, to the total weight of xylene and ether, which was tetrahydrofuran, about 22-40% by weight in the reaction mixture. I.e. the reaction mixture consisted predominantly from tetrahydrofuran. It has now been found that the reaction is very beneficial advances as the amount of diluent, e.g., xylene, adds to the total weight of diluents and ether, e.g. tetrahydrofuran, in the reaction mixture 50 - 80 wt%, e.g., 60-76 wt%, although such percentages are also useful some of which falls outside the range, e.g., 30-80% by weight.

The addition of cycloalkyl magnesium halide Grignard compound to the Tin halide is usually used at a temperature up to 1050C, such as 200C - 1050C, e.g. 400C - 950C and in particular 70 - 850C.

The solution of the Grignard compound usually becomes the tin (IV) halide and slowly added to the diluent at a rate sufficient to in order to keep the reaction mixture at the temperature mentioned. The reaction can if necessary, be carried out under pressure and the reaction temperature is at atmospheric pressure above the boiling point of the mixture of ether and liquid Thinners, to keep the mixture liquid. Appropriate is in the preferred process in which the ether has a boiling point below 900C has added the Grignard compound sufficiently quickly that the reaction mixture boils, the ether being refluxed. When using the preferred Ether, tetrahydrofuran, the temperature of the reaction liquid is in the range from 75 - 850C.

According to a preferred embodiment of the method, the ether has a boiling point below that of the diluent and it becomes at least some, e.g. some, and preferably a major proportion of the ether in the After the addition of the Grignard compound, the reaction mixture evaporates and leaves a medium back, which contains tricycloalkyltin halide but is depleted in ether. Usually 20-90% by weight of the ether are evaporated, in particular 50-80% by weight.

While evaporation can occur under reduced pressure, will it is usually achieved in that the mixture of ether, diluent and Reaction product heated to a second reaction temperature under atmospheric pressure which is above the boiling point of the ether, so that the ether distils off and the distillate can be collected for reuse. The second temperature is usually in the range of 60-1500C, e.g. 90-1500C, preferably 105 - 1500C and especially 110 - 1500C. Usually the reaction mixture if the ether has been distilled off at the second reaction temperature via a a sufficient period of time, e.g., at least 0.5 hours, preferably 14 hours. Further heating under reflux conditions is expedient for the liquid carried out in the reaction mixture, the liquid usually contains a major part of the diluent and a small part of the ether. The total time it takes to heat the reaction product above 1050C is usually 0.5-5 hours. This preferred embodiment of the method by evaporation at least part of the ether is especially suitable when the ether is one which is completely miscible with water, e.g. Dioxane or tetrahydrofuran.

According to an alternative but less preferred embodiment During the process, the reaction mixture is heated to 40-1500C, e.g. 90-1500C, such as 105 - 1500C and especially 110-1500C for at least 5 minutes, e.g. 5 minutes to Heated for 24 hours without the ether evaporating, if necessary Pressure is applied to keep the mixture fluid and prevent evaporation.

After heating with or without evaporation of the ether, the reaction mixture becomes worked up to obtain the tricycloalkyltin halide by treating it with a aqueous acid is brought into contact, e.g. with water and some acid to hydrolyze any unreacted Grignard compound and / or tin (IV) halide and to form an organic phase comprising the organotin product and the diluent and the ether (if present) as well as an aqueous acidic phase, the magnesium chloride and contains the ether, if any, if it is to any extent is water soluble. The phases are then separated. According to a preferred embodiment the procedure is then, when at least a part of the ether has been evaporated, the reaction medium contains a reduced ether content at the end of the reaction, which is advantageous because then most of the ether during the evaporation stage can be recovered and, if the ether is water-soluble, only a small amount Amount and, ideally, nothing at all is lost in the aqueous phase. The tricycloalkyl tin halide can be isolated from the organic phase. The aqueous phase can be removed by stripping be freed of volatile solvents, e.g. if ether is present, and the ether can be used again.

According to an alternative embodiment of the method can the Tricycloalkyltin halide with or without isolation from the organic phase directly converted into the corresponding hydroxide by hydrolysis, e.g. by contact with aqueous alkali, such as sodium hydroxide, with heating, e.g., to reflux temperature. Thus, the organic phase containing the tricycloalkyltin chloride can slowly over a period of 1 - 2 hours to an aqueous alkali solution at 70 - 1000C, e.g. 80-900 C are added and then 0.5-2 hours at reflux temperature be heated. At the end of the hydrolysis it may not be in an aqueous solution Alkali metal halide can be dissolved by adding sufficient water. The product The hydrolysis is then converted into an organic phase containing the tricycloalkyltin hydroxide contains, and an aqueous phase is allowed to separate, after which the phases are separated will. The tricycloalkyltin hydroxide can then from the organic phase can be obtained, e.g. by evaporation of the solvent. It can be cleaned e.g. by washing with water and / or recrystallization, if so desired.

A most preferred embodiment of the method according to the invention is that 2.8-3.05 moles of cyclohexyl magnesium chloride in tetrahydrofuran per mole of tin (IV) chloride in xylene are added, the amount of tin (IV) chloride to xylene is 10-25% by weight and the addition is carried out with stirring at 70-850C will. This gives a reaction mixture from which most of the Tetrahydrofuran is evaporated and a medium is obtained which is tricyclohexyltin chloride contains. The medium is then treated with aqueous acid, whereby a aqueous phase and an organic phase which contains tricyclohexyltin chloride, is obtained and the phases are then separated.

The tricycloalkyltin halides or hydroxides according to the invention Processes have been established, can as a fungicide or as a Intermediates used to make other tricycloalkyltin compounds will.

The invention is illustrated in more detail by the following examples, with parts being by weight.

Example 1 Cyclohexylmagnesium chloride was produced in a reactor which is provided with a stirrer, a heater and a reflux condenser was. The contents of the reactor were kept under a nitrogen atmosphere. The reactor was filled with 72.9 parts of magnesium. To this end, 10.0 parts of cyclohexyl chloride, 8.1 Parts of cyclohexyl bromide and 83.1 parts of tetrahydrofuran were added. After introduction the reaction became a mixture of 339.6 parts of cyclohexyl chloride and 670.7 parts Tetrahydrofuran at a rate sufficient to keep the mixture steady to keep at reflux, added.

The mixture was then refluxed for 1 hour. After cooling, the reaction mixture was filtered, the filtrate being a solution from cyclohexyl magnesium chloride in tetrahydrofuran.

It became a reactor equipped with a stirrer, a heater and a reflux condenser and its contents kept under nitrogen was, with a solution of 260.7 parts of tin (IV) chloride in 1500 parts of xylene loaded.

The solution was stirred and it became the solution of cyclohexyl magnesium chloride added at such a rate that the reaction temperature is initially 850C did not exceed, the rate being sufficient, with sufficient addition of tetrahydrofuran continue to boil under reflux conditions. At the end of the addition, the 1.5 hours took, the reaction temperature was slowly increased to 1200C while distilling off of tetrahydrofuran. The mixture was refluxed for a total of 2 hours at 1200C heated after the addition was complete, after which a mixture was obtained which reduced a Had proportion of tetrahydrofuran. That The reaction mixture was heated to 300C cooled and this was a mixture of 645 parts of water and 33.0 parts of 30% strength Hydrochloric acid added with cooling. The organic phase formed was from the formed separated aqueous phase and filtered, a solution of tricyclohexyltin chloride from which the chloride was obtained by evaporation of the solvent can be.

The tricyclohexyltin chloride was converted to the tricyclohexyltin hydroxide by adding the organic solution of the chloride to a mixture of 45 parts Sodium hydroxide, 45 parts of water at 80-850C over a period of 1 1/2 hours convicted.

The resulting mixture was refluxed for 1 hour and thereafter / allowed to cool and 162 parts of water was added to remove the sodium chloride to solve. The aqueous and organic phases formed were separated and the organic phase evaporated to dryness leaving a solid raw substance, which was washed with water and then dried and 350 parts of tricyclohexyltin hydroxide (90% pure, 91% yield).

Examples 2-5 and Comparative Examples A-C The method of preparation of tricyclohexyltin chloride according to Example 1 was with different amounts Tetrahydrofuran and xylene and / or different heat treatments at the end of the Repeated addition of the cyclohexyl magnesium chloride. In each case it was a cyclohexyl Grignard compound prepared in tetrahydrofuran from magnesium (24.3g, Ig atom) and as in the example 1 was added to a solution of tin (IV) chloride (86.9 g, 0.33 mol) in xylene. At the At the end of the addition, the temperature was kept at 80 ° C. (Example 4) or at the in the following table increased temperatures, with in the examples 3 and in Comparative Example A, the tetrahydrofuran distilled off was collected. The length of time the reaction continued after the addition was this same, namely 2 hours in each case. At the end of the heat treatment in In each case, the reaction mixture was worked up according to Example 1 and the organic Phase analyzed by gas chromatography. The solution of crude tricyclohexyltin chloride was evaporated and the crude yield of tricyclohexyltin chloride was determined.

At- THFx) xylene wt .-% wt .-% wt .-% Erhit product analysis (gas chrom.) Rohausspiel SnCl4 Grignard Xylene- wt .-% loot g g rel. Conn. regarding temp. xx) g% cHex4% cHex3% cHex2 THF + THF ° C after Sn Sn Cl Sn Cl2 addition 2 254.6 387.0 22.45 56.1 60.3 93 4.8 91.3 4.0 119.2 3 254.6 387.0 22.45 56.1 60.3 135 4.6 91.8 3.6 116.0 A 180.2 273.6 31.7 79.2 60.3 120 20.5 75.7 3.8 102.5 B 387.5 258.0 33.7 36.8 40.3 95 23.7 70.5 5.8 118.9 4 753.6 387.0 22.45 18.9 33.9 80 6.5 90.5 3.0 120.5 5 254.6 774.0 1.2 56.1 75.2 110 2.7 94.3 3.0 125.0 C 254.6 129.0 67.4 56.1 33.6 about 28.0 66.8 5.1 117.0 90 x) THF = tetrahydrofuran xx) cHex = cyclohexyl the Results in the table show the large increase in yield and increase in purity of tricyclohexyltin chloride, which can be achieved with reactions, being solutions of SnCl4 in xylene with less than 25% SnCl4 based on xylene are compared with reactions in which more than 25 wt.% SnCl4 is present in xylene.

Claims (11)

Claims: 1. Process for the production of triorganotin halides by reacting a cycloalkyl magnesium halide Grignard compound in which the cycloalkyl group has a cyclohexyl group or an alkyl-cyclohexyl group 1 - 3 alkyl groups of 1 - 4 carbon atoms each and in which the Halide is a chloride, bromide or iodide, with a tin (IV) halide, in which the halide is chloride, bromide or iodide, in the molar ratio 3 + 0.3: 1 such that the cycloalkyl magnesium halide dissolved in an ether as a solvent to the tin (IV) halide in an inert liquid diluent adds, characterized in that in the reaction of the cycloalkyl magnesium halide selects such proportions with the tin (IV) halide in the diluent, that the tin (IV) halide is less than 25% by weight of the diluent and that the addition is carried out with stirring, so that a reaction mixture containing Tricycloalkyl tin halide is formed. 2. The method according to claim 1, characterized in that as Ether tetrahydrofuran is used. 3. The method according to claim 1 or 2, characterized in that one used a liquid hydrocarbon as a diluent. 4. Process according to claims 1-3, characterized in that an ether with a boiling point below that of the diluent used and that at least part of the ether evaporated in the reaction mixture is leaving behind a reaction medium depleted of ether. 5. The method according to claim 4, characterized in that the Reaction medium then treated with an aqueous acid and from the formed organic phase containing tricycloalkyltin halide, the aqueous Phase separates. 6. The method according to claim 1-5, characterized in that one the addition of the cycloalkyl magnesium halide to the tin (IV) halide at 40-1050C performs. 7. The method according to claim 1-6, characterized in that one a weight ratio of the diluent to the total amount of diluent and ether of 50-80% by weight. 8. The method according to claim 1-7, characterized in that one the reaction mixture is kept at 90 ° -1500 ° C. after the addition. 9. Process according to claims 1-8, characterized in that a weight ratio of tin (IV) halide to diluent of 15-25 % By weight. 10. The method according to the preceding claims, characterized in that that 2.8-3.05 moles of cyclohexylmagnesium chloride in tetrahydrofuran per mole of tin (IV) chloride in xylene, the amount of tin (IV) chloride to xylene being 10-25% by weight, that the addition is carried out with stirring at 70-850C, that the obtained Reaction mixture evaporates a larger proportion of the tetrahydrofuran that the remaining reaction medium, which contains tricyclohexyltin chloride, treated with an aqueous acid and that the aqueous phase formed of the organic phase, which contains tricyclohexyltin chloride, is separated off. 11. Process for the production of triorganotin hydroxide compounds, through this characterized in that a triorganotin halide that according to claims 1 - 10 is treated with aqueous alkali.