DE1670296A1 - Process for the preparation of substituted phosphinimines and corresponding amidophosphonium halides - Google Patents

Description

Process for the preparation of substituted phosphinimines and corresponding Amidophosphonium Halides This invention relates to a process for the preparation of substituted phosphinimines and corresponding amidophosphonium halides by reacting amines with trisubstituted phosphines and halogen.

It is known that phosphinimines or their salts, the amidophosphonium salts, by reacting trisubstituted phosphines with azides (Helvetica Chimica Acta, Volume 2, page 635 (1919); Volume 4, page 861 (1921)) or chloramines (Angewandte Chemie, Vol. 71, p. 374 (1959); Journal of the American Chemical Society, vol 81, p. 2982 (1959); Journal of the American Chemical Society 1937, p. 527) can produce.

Other manufacturing processes are the conversion of triphenylphosphine with hydroxylamine-0-sulfonic acid (Liebigs Annalen der Chemie, Volume 618, page 53 (1958)) or O, tT-dibenzylhydroxylamine (Chemistry and Industry 1956, page 1014), the implementation of triphenylphosphine dihalides with primary arylamines (Liebigs Annalen der Chemie, Volume 627, page 142 (1959)) or the implementation of Phosphinigsäureamiden with alkyl halides (Journal of Organic Chemistry, Volume 26, page 4733 (1961)).

Amidophosphonium salts can also be formed by the addition of hydrohalic acids or alkyl halides on phosphinimines (Helvetica Chimica Acta, Volume 4, page 861 (1921); Angewandte Chemie, Volume 68, page 473 (1956); Liebigs Annalen der Chemie, Volume 627, page 142 (1959)). Conversely, one obtains by splitting off of acids with the help of bases from amidophosphonium salts phosphinimines (German U.S. Patent 1,192,203; Angewandte Chemie, Volume 71, page 626 (1959)).

All of the processes mentioned are based on raw materials that are difficult to access off or. require several reaction stages in order to obtain the desired substances. Some starting materials, e.g. B.

Azides and chloramines must be implemented with special precautions will.

It has now been found that substituted phosphinimines of the general formula where R1 and the individual radicals R2 can be identical or different and each represent an aliphatic, cycloaliphatic, araliphatic or aromatic radical, R1 can also denote a heterocyclic radical and n stands for 1, 2, 3 or 4, and / or theirs corresponding amidophosphonium halides can advantageously be prepared if primary amines of the general formula Ri- TH2) n II, in which R1 and n have the aforementioned meaning, with trisubstituted phosphines of the general formula in which the individual radicals R2 have the aforementioned meaning and converts halogen.

The conversion can be represented in the case of the use of aniline, triphenylphosphine and chlorine by the following formulas: Compared to the above-mentioned processes, the process according to the invention, starting from more readily available starting materials, provides a higher number of substituted phosphinimines and amidophosphenium halides in better yield and purity and in one reaction stage.

Primer amines are used as Auspanpsstoffe II. Preferred amines II and accordingly preferred end products I are those in their Formula R1 is an alkyl, cycloalkyl, aralkyl or aryl radical, each with up to 10 carbon atoms or a preferably 5- or 6-membered heterocyclic Ring that contains 1 to 3 nitrogen atoms and is also replaced by 1 or 2-alkyl, cycloalkyl, Aralkyl or aryl groups each with up to 12 carbon atoms can be substituted can means. The residues mentioned can be used in the preferred starting materials II and / or the heterocyclic ring is in each case also substituted by 1 to 4 amino groups be. These amino groups can also be reacted according to the process of the invention will.

So you can z. B. use the following primary amines as starting materials II : 2-aminopyrimidine, cyclohexylamine, aniline, hexamethylenediamine, melamine, benzoguanamine, Isobutylamine, octylamine, benzylamine, «-naphthylamine, benzylguanamine, acetoguanamine, 2-Amino-4, 6-diethylpyrimidine, benzidine, p-toluylamine, p-nitroaniline, p-chloroaniline.

Trisubstituted phosphines are used as starting materials III.

Preferred phosphines are those in whose general formula III the individual radicals R2 can be identical or different from one another and in each case an alkyl, cycloalkyl, aralkyl or aryl radical, each with up to 12 carbon atoms mean. In general, the phosphines are used in stoichiometric amounts, based on the primary amines II; you can also use a small excess up to Use 2 mol%. If the starting material II has several amino groups, the must The amount of phosphine used is increased according to the number of amino groups, to get to di- or polyphosphinimines.

It can e.g. B. used the following phosphines as starting materials III be: triphenylphosphine, tri-n-butylphosphine, tricyclohexyl-, tribenzylphosphine, P-n-Butyl-P-dlEthylphosphine ,.

P-phenyl-P-ethyl-P-n-butylphosphine, triethylphosphine, trioctylphosphine.

Another starting material used is halogen, bromine as a preventative or chlorine. The reaction is generally carried out with halogen in a stoichlometric amount, based on starting material III, carried out; you can also use a small excess use up to 2 mol%. If the starting material II has several amino groups, it must the amount of halogen can be increased according to the number of amino groups.

Halogen is subject to zuerat with the starting materials II and III Elimination of hydrogen halide to the corresponding amidophosphonium halides around. If the temperature is increased, they form with further elimination of hydrogen halide the phosphinimines. This occurs depending on the constitution of the amidophosphonium halide Conversion to phosphinimine at lower or higher temperature, in general the phosphonium salt and bel are obtained up to temperatures between 130 and 170 ° C Temperatures of 170 ° C from the corresponding phosphinimine. If you use the Reaction of the solution agent, the formation of the phosphinimine is somewhat favored, the more polar the solvent is. If starting material II is a polyamine, then the Implementation takes place at each amino group, with the implementation rate from the temperature, optionally the solvent and the constitution of the compound depends. By a suitable choice of the conditions and the reaction time, one can Yerbindungen obtained, the amidophosphonium and / or phosphinimine groups and optionally also contain free amino groups in the Molukül.

The reaction is usually bel a temperature between 70 and 250 ° C, preferably between 90 and 180 ° C, without pressure or under pressure, continuously or carried out batchwise. It is expedient to use under the reaction conditions inert organic solvents such as aromatic hydrocarbons, e.g. B. benzene, Chlorobenzene or dichlorobenzene, mitrobenzene; Chlorinated hydrocarbons, e.g. B. carbon tetrachloride, Trichlorahane, tetrachloroethane; Benzonitrile, diphenyl, sulfolane, diphenyl sulfone ; Xther, e.g. B. Diphenyl ether.

The elimination of hydrogen halide can be accelerated by suitable measures will. You can z. B. the flow of a gas inert under the reaction conditions vie pass nitrogen or argon through the reaction space. In the case of manufacture of phosphinimines, the gas is introduced before the start of the reaction To remove oxygen from the reaction space. You can also do the implementation in the presence of the hydrogen halide binding compounds, e.g. B. tertiary amines such as pyridine, Triethylamine; inorganic amides or hydrides, such as sodium amide, magnesium hydride, carry out.

The reaction can be carried out as follows: To a mixture the starting materials II and III, optionally together with solvent and the hydrogen halide binding compounds, the halogen becomes, optionally together with solvent. The reaction mixture is then added under, pass and optionally heated to the reaction temperature with the addition of inert case. The reaction is complete after 1 to 24 hours. The reaction mixture becomes the Solvent distilled off and the remaining end product from suitable solvents, z. B. water, petroleum ether, chlorobenzene, recrystallized.

If the end product separates on completion of the reaction and cooling of the reaction mixture in residual form, it is filtered off and processed in an analogous manner Way cleaned. The filter material can also be dissolved in ethyl alcohol, the The end product is then precipitated with sodium hydroxide solution and purified in the manner described above.

The known and new ones which can be prepared by the method of the invention Compounds are valuable starting materials in the four dite manufacture of antistatic agents in the plastics field and flame retardant auxiliaries.

The parts mentioned in the following examples are parts by weight.

example 1 43; 6 parts of 2-aminopyrimidine and 26.23 parts of triphenylphosphine are suspended in 200 parts of m-dichlorobenzene. After adding 15.98 parts of bromine with stirring and passing a stream of dry nitrogen through the reaction mixture, the mixture is heated to 160 ° C. for 24 hours. The solvent is then distilled off in vacuo and the residue that remains is recrystallized from water. 38 parts (49% of theory) of P-triphenyl-pyrimidine- (2) -amido-phosphonium bromide are obtained in colorless crystals (melting point 205 ° to 207 ° C.).

Example 2 16 parts of bromine, diluted with 50 parts of chlorobenzene, are slowly added to a solution of 9.92 parts of cyclohexylamine, 26.2 parts of triphenylphosphine and 7.71 parts of pyridine.

The reaction mixture is stirred and passed through a dry A stream of nitrogen heated to 90 ° C for one hour. After cooling, the formed The solid is filtered off, washed with water and recrystallized from water. Man receives 44 parts (91% of theory) triphenylcyclohexylamidophosphonium bromide in Form of colorless crystals with a melting point of 177 ° C. i Example 3 C6H5-N = P (C6H5) 3 To a solution of 9.3 parts of aniline, 26.2 parts of triphenylphosphine and 20, 2 Parts of triethylamine in 200 parts of carbon tetrachloride will 16 parts of bromine were slowly added. A weak stream of nitrogen flows through the solution directed to displace the oxygen in the air. The reaction mixture is 30 minutes heated to reflux (77 ° C). After cooling the mixture, the formed The solid is filtered off and the filtrate is concentrated in vacuo. The end product remains as brown b1 back. After recrystallization from PetrolSther (b.p. 60 to 95 ° C) 23.3 parts (66% of theory) of the N-phenyltriphenylphosphinimide are obtained as colorless crystal powder with a melting point of 131 ° C.

Example 4 11.6 parts of hexamethylenediamine and 52.46 parts of triphenylphosphine are suspended in 300 parts of chlorobenzene together with 15.82 parts of pyridine. While stirring and at the same time passing a stream of dry nitrogen through it, 31.96 parts of bromine are slowly added to the mixture. After heating under reflux (132 ° C) for 5 hours, the solvent is distilled off in vacuo. The residue is recrystallized from water.

There are 61 parts (76% of theory) 1,6-hexamethylenediamidobis-ctriphenylphosphonium bromide] obtained with a melting point of 132 ° C.

Example 5 To a separation of 12.6 parts of melamine, 40.4 parts of tri-n-butylphosphine and 15.82 parts of pyridine in 300 parts of m-dichlorobenzene, 31.97 parts of bromine diluted with 50 parts of m-dichlorobenzene, slowly admitted. The reaction mixture is refluxed for 4 hours at 175 ° C. with stirring. After cooling, the solid formed is filtered off with suction and washed out well with water. 65 parts (94% of theory) of the [2-amino-4,6-bis (N-tributyl-amidophosphonium) -1,3,5-triazine] dibromide are obtained as a colorless crystalline end product with a melting point of 299 to 301 ° C (can be recrystallized from nitromethane).

Example 6 To a slurry of 17.5 parts of benzoguanamine and 52.46 parts of triphenylphosphine in 350 parts of dichlorobenzene, 15.98 parts of bromine, diluted with 50 parts of the same solvent, are slowly added with stirring. The reaction mixture is then heated under reflux at 172 ° C. for 12 hours while stirring and passing a stream of dry argon or nitrogen through it. Hydrogen bromide is split off and the reaction mixture forms a solution. The solvent is then filtered off in vacuo. The remaining solid end product is completely dissolved in a sufficient amount of ethyl alcohol. By adding 10 parts of concentrated sodium hydroxide solution (40% by weight), a crystal slurry consisting of fine, colorless Iladeln precipitates out of the solution. The crystals are filtered off, washed well with cold water and dried. 76 parts (96% of theory) C2-phenyl-4-triphenylamidophosphonium) -6- (triphenylphosphinimino) -1, 3, 5-triazine bromide are obtained in the form of colorless crystal needles with a melting point of 268 ° C.

Example 7 @ 10.64 parts of chlorine are passed into a suspension of 12661 parts of melamine and 78.69 parts of triphenylphosphine in 400 parts of dichlorobenzene. The Chjr is fed through an -in inlet tube to the bottom of the reaction vessel. Before the introduction of chlorine, the atmospheric oxygen is displaced from the reaction vessel by a stream of dry argon or nitrogen. The reaction is stirred during the reaction. After the addition of chlorine (about 1 hour), the mixture is od while passing an argon through. The nitrogen stream was heated to reflux (172 ° C.) for 12 hours. The elimination of hydrogen chloride is then complete. The reaction mixture is cooled to room temperature, filtered off with suction and the filter material is recrystallized from chlorobenzene. 90 parts (92% of theory) of; -Triphenylphosphinimino-4,6-bis (N-triphenylamidophosphonium) -1, 3, 5-triazine] dichloride are obtained in shiny silver flakes (melting point 302 ° C.).

Claims (1)

Process for the preparation of substituted phosphinimines of the general formula where R1 and the individual radicals R2 can be identical or different and each represent an aliphatic, cycloaliphatic, arallphatic or aromatic radical, R @ can also denote a heterocyclic radical and only stands for 1, 2, 3 or 4, and / or their corresponding amidophosphonium halides, characterized in that primary amines of the general formula R1 - (@ H2) n II, in which RI and n have the aforementioned meaning, are substituted with trisubstituted phosphines of the general formula in which the individual radicals R2 have the aforementioned meaning and converts halogen.