DE2357678C3 - Process for the production of alkene phosphonic acid chlorides and alkene phosphonic acid chlorides - Google Patents

Description

H C!

in which R _{1 is} chlorine, an alkyl group having 1-18, in particular 1 or 2, carbon atoms, or a phenyl or benzyl group which is optionally substituted on the aromatic ring, and R _{2 has} an alkyl group

1 - 10, carbon atoms, or hydrogen, by catalytic elimination of hydrogen chloride from compounds of the general formula (II)

Η — C — C — P 9 ^R.

(H)

Cl

CI

in which R ₁ and R _{2 have} the above meaning, characterized in that the catalysts used are those compounds which contain at least one 3- to S-bonded nitrogen atom or one 5-bonded phosphorus atom, which in the case of nitrogen has 1-4 valences, in the case of of phosphorus is bonded with at least 3 valencies to organic, optionally substituted radicals with up to 20 carbon atoms, 2 of these valences being able to form a double bond, or 1 to 3-base organic or inorganic fully amidated acids of 3 to 5 valent phosphorus whose N Atoms can be alkylated by optionally substituted aliphatic radicals with up to 20 carbon atoms and the optionally substituted organic radicals thereof can contain up to 20 carbon atoms.

It is known that vinylphosphonic acid dichloride and vinylphosphinic acid chlorides can be split off of hydrogen chloride from the corresponding 2-chloroethane phosphonic or phosphinic acid chlorides can produce with the help of stoichiometric amounts of tertiary amines in inert solvents

R '

/
ClCH ₂ CH ₂ PCl ₂ + NR "■

O R "'

(G eft he and co-workers, Z. obsc. Chim. 31 [1961), No. 3, pp. 955-958; Swiss patent 3 91 699; DE-OS Il 58 509).

These reactions can be shown schematically as follows:

R '

\
CH ₂ = CHPCl ₂ + R "-N · HCl

O R '"

R '

/
P-Cl + N-R "

/ Il \

ClC ₂ H ₄ OR "'

R '

- ♦ P-Cl + R "-N ■ HCl

/ Il /

CH ₂ = CH O R '"

The amounts of amine required for the cleavage, the separation of the amine hydrochloride, the recovery of the free amine and the distilling off of the solvent used make these processes uneconomical and cumbersome. Furthermore, the Swiss Patent Specification 3 91 699 discloses the elimination of hydrogen chloride from 2-Chlorpropanphosphonsäuredichlorid by heating at 200 ⁰ C to form Propenphosphonsäuredichlorid. The required reaction time of around 15 hours is uneconomical. In addition, this long reaction time and the high reaction temperature in the production of more sensitive alkene phosphonic acid chlorides, such as vinyl phosphonic acid dichloride, lead to substance losses due to excessive resinification and occasionally also to deflagrations.

DE-OS 15 68 945 describes a significant reduction in the reaction time by heating 2-Chloräthanphosphonsäuredichlorid in the presence of triphenylphosphine as a catalyst. Triphenylphosphine however, it is a difficult connection to make.

The invention now relates to a process for the catalytic production of vinyl groups containing Acid chlorides of phosphorus of the general formula (I)

OR ₁

ii /

C = CH-P

H Cl

(D

in which R _{t is} chlorine, an alkyl group with 1-18, preferably 1-4, in particular 1 or 2 carbon atoms, or a phenyl or benzyl group optionally substituted on the aromatic ring, and R _{2 is} an alkyl group with 1-10, preferably 1 —4C atoms, preferably methyl, or hydrogen, by catalytic splitting off of hydrogen chloride from compounds of the general formula (II)

R ₂ HOR ₁

V ι ii /

c-c-ρ

/ I I \

H Cl H Cl

(H)

in which R ₁ and R _{2 have} the above meaning, which is characterized in that the catalysts used are those compounds which contain at least one 3- to S-bonded nitrogen atom or one 5-bonded phosphorus atom, which in the case of nitrogen has 1-4 valences, in the case of phosphorus with at least 3 valences is bound to organic, optionally substituted radicals with up to 20 carbon atoms, 2 of these valences being able to form a double bond, or 1 to 3-base organic or inorganic fully amidated acids of the 3- to 5-valent Phosphorus, the N atoms of which can be alkylated by optionally substituted aliphatic radicals with up to 20 carbon atoms and whose optionally substituted organic radicals can contain up to 20 carbon atoms, are used. The nitrogen and phosphorus compounds which are catalytically active according to the invention can be represented schematically by the general formulas (III), ( ¹ V;, (V) and (VI)

X
ι ω
γβ R ₁ = X I.
R ₃ (IV) (III) Ri
R ₁ -XR ₃ \ / ²
X
R ₃ R ₄ Il
Z

(V)

where for X = N one of the ligands R ₁ , R ₂ , R _{3 can be} the radical of an optionally polybasic carboxylic acid or the radical of an inorganic or organic acid of trivalent or pentavalent phosphorus or its optionally alkylated amides,
R _{4 is} an organic radical having 1-20 carbon atoms, or H, when X = N and R ₂ and R _{3 are} each an organic radical, Z is oxygen or, when X = P, sulfur or 2 halogen atoms or NR ₅ , where R ₅ = H or a

ίο can be an organic radical with 1-20 carbon atoms.

For X can therefore be an N or P atom, for Y an inorganic or organic acid radical, z. B. a halogen ion, an SO ₄ ion, a methyl sulfate ion or the ion of an organic sulfonic acid.

R ₁ , R ₂ , R ₃ , R * and Rj can represent the same or different organic radicals, e.g. B. straight-chain or branched alkyl groups with 1-20 carbon atoms, preferably 1-12, especially 1-4 carbon atoms, alkenyl groups with 2-20, preferably 2-12, especially 2-4 carbon atoms, cycloalkyl or - alkenyl groups with 4-8, preferably 4-6 carbon atoms, aryl or aralkyl groups with 6-20, preferably 6-12 carbon atoms or acyl groups with 1-4, preferably 1 or 2 carbon atoms, all radicals R ₁ to R _{5 in} turn, preferably by halogen, in particular chlorine and / or bromine or alkoxy radicals with 1-4 carbon atoms, preferably 1-2 carbon atoms, or a dialkylamino group with alkyl groups of 1-4 carbon atoms, preferably substituted once substituted, can be.

Two of the radicals R ₁ to R _{5 can be} members of a heterocyclic ring of aromatic or cycloaliphatic nature, which contain further heteroatoms, e.g. B.

Nitrogen, oxygen or sulfur. If X = nitrogen, R ₂ and / or R ₃ and, if R ₂ and R _{3 are} organic radicals, R _{4 can also} mean hydrogen.

Z can stand for oxygen or, if X is phosphorus, also for sulfur, two halogen atoms, preferably 2 chlorine atoms, or for the group NR ₅ , where R ₅ = H or an organic radical with 1-20C atoms.

If X is nitrogen, one of the radicals R ₁ to R _{3 can be} an acid amide radical or acid diamide radical of an organic acid of trivalent or pentavalent phosphorus, the N atoms of which have alkyl groups with 1-18 carbon atoms, preferably 1-4 carbon atoms. Atoms, can be substituted. Preference is given to compounds in which the amide group (s) are mono-, in particular disubstituted, in the manner described.

The catalytically active compounds according to the invention can also be several identical or different Contains elements of the meaning X. The molecular weight of the catalyst used is preferably up to 500, in particular up to

(VI)

in which X is nitrogen or, in formulas V and VI, phosphorus, Y is an inorganic or organic acid residue, R _{1 is} an organic residue with 1-20 carbon atoms, R ₂ and R _{3 are} each an organic residue with 1-20 carbon atoms. Atoms or H if X = N,

The catalysts according to the invention can be used, for example:

Amines such as trimethylamine, triethylamine, tripropylamine, Tributylamine, dimethylethylamine, diethylbutylamine, diethyldodecylamine, N-dimethylaniline, 4 - methyl - N - dimethylaniline, N - diethylaniline, Ν, Ν'-tetramethyl-p-phenylenediamine, triphenylamine, Diethylamine, n-butylamine.

¹ heterocyclic nitrogen compounds, such as pyridiii. Quinoline, isoquinoline and their alkyl or dialkyl, preferably methyl or dimethyl derivatives,

Imidazole, N-vinylimidazole, benzimidazole, benzthiazole, Benztriazole, 2-amino-6-ethoxybenzthiazole, 2-hydroxy-5,7-dimethylpyrazolo (l, 5, a) pyrimidine, N-methylpyrrolidine. N-ethylpiperidine, pyrrolidinocyclohexene, Triazole, piperidine and their oxides, ζ. Β. Pyridine oxide.

Acid amides, ζ. B. dimethylformamide, diethylformamide, Diethylpropionamide, N-dimethylbenzamide, Ν, Ν'-tetramethylterephthalic acid diamide, hexamethylphosphoric acid triamide, Ethanephosphonic acid bisdiäthyemid, Methanbutanphosphinigsäuredimethylamid, Di-Äthylphosphinigsäureisobutylamid, or Ureas such as tetramethylurea and N ^ '^' - methyl-N-phenylurea.

Quaternary ammonium salts, e.g. B. tetramethylammonium chloride or bromide, trimethylbenzylammonium chloride, triethylbenzylammonium chloride or bromide, trimethylchloromethylammonium chloride.

Quaternary phosphonium salts, e.g. B. Tetraäthylphosphoniumchlorid, Trimethylbenzylphosphonium chloride, triphenylethylphosphonium-2,4-diaminobenzene sulfonate.

Organic compounds of pentavalent phosphorus, e.g. B. triniethylphosphine oxide, tributylphosphine oxide, Trihexylphosphine oxide, triphenylphosphine oxide, dimethylphenylphosphine oxide, dimethylchloromethylphosphine oxide, Dimethylhexylphosphine oxide, dimethyldodecylphosphine oxide, dimethyleikosylphosphine oxide, Dimethylpyrrolidine-1-methylphosphine oxide, Dimethylphenylphosphine sulfide, DimethyWodecylphosphineulfid, 2-DimethyIphosphinylpropionäuremethylester, l-methylphospholene-3. l-EthyI-3-methylphospholen-3,2-fluorosulfonylethyldimethylphosph: noxide, N - 2 - dimethylphosphinylethyl - N - methylacetamide, N-2-dimethylphosphinylethylmethylamine, Triphenylphosphine dichloride, dimethylchloromethyldichlorophosphorane, triphenylphosphineimine, triphenyl-n-2-hydroxyethylphosphineimine.

Especially preferred! among these compounds are triethylamine and triethylamine hydrochloride. Preference is also given to the other, including the mixed, tri- (C2-C ₄ ) -alkylamines, the trialkylphosphine oxides, in particular the trimethylphosphine oxide, and their HCl adducts, and also mixtures of these compounds.

The catalysts of the invention are used in amounts of 0.01-5% by weight or more, based on the compound of the formula (II) used, preferably used in amounts of 0.05-2% by weight. They can be used as such or in the form of their salts, preferably their hydrochlorides.

The inventive process is in general carried out in a simple manner such that is added to a compound of formula (II) with one of said catalysts, the reaction mixture heated at temperatures of about 150 ° to 200 "C, preferably 160" - 19O ⁰ C , in a manner known per se, hydrogen chloride and the corresponding vinyl compound of the formula (I) are distilled off. If the distillation is carried out under reduced pressure, lower! the transition temperature changes accordingly and the reaction proceeds more rapidly. A particular economic advantage of the claimed process is the possibility that, instead of pure 2-chloroalkanephosphonic or phosphinic acid chloride, one can start from crude products obtained by phosgenation of 2-chloroalkanephosphonous or phosphinic acid chloride (7. B. according to DE-OS 21 32 962; DE-OS 22 15 314; DE-OS 21 29 583; P 22 25 545.4), which may already contain the catalyst to be used according to the invention for the HCl elimination from their production so that - especially in the case of the phosphonic acid diilorides - further catalyst additives can be unnecessary.

A particularly preferred variant of the method is permitted esi therefore, the proiikl obtained for example by the 4 procedures mentioned above, to which the catalysts of the invention have already been added in the previous phosgenation reaction have been, without intermediate cleaning and without changing the reaction vessel in the manner of a so-called Implement one-pot process directly to vinyl compounds of the formula (1), such as the following Examples show.

The alkene phosphonic and phosphinic acid chlorides obtained by the process of the present invention are valuable intermediate products for flame retardants, pesticides, detergents, flotation auxiliaries and plastics.

The invention is illustrated by the following examples:

example 1

137 g of phosphorus trichloride are reacted with 135 g of ethylene oxide to form tri (chloroethyl) phosphile. The reaction product is rearranged at 140 ° 145 "C to chloroethane phosphonic acid di (chloroethyl) ester and converted into chloroethane phosphonic acid dichloride according to the process of DE-OS 21 32 962 with phosgene in the presence of 2 g of triethylamine as catalyst. The reaction mixture already containing triethylamine as catalyst is then heated to about 200 ° -220 ⁰ C bottom temperature. Under evolution of hydrogen chloride distilled at a head temperature of 170'-180 ⁰ C and at normal pressure in the course of 3 hours 143 g of a colorless liquid over after gaschronnatographischer analysis 80% vinylphosphonic acid dichloride (89% of theory based on PCI3) and 9% 2-chloroethane phosphonic acid dichloride (6% of theory) and from which 128 g vinylphosphonic acid dichloride are obtained by fractionation under reduced pressure. One leads this split under reduced pressure of 400-500 Torr, the reaction time can be shortened to 1.5 hours with the same yield and lower distillation temperature.

Including the recovered chloroethane phosphonic acid dichloride the bulge in vinylphosphonic acid dichloride is 93.5% of theory, based on the PCI3 used.

Example 2

260 g of phosphorus trichloride are reacted analogously to Example (1) with 255 g of ethylene oxide, and the adduct is rearranged and 500 g of crude 2-chloroethane phosphonic acid di-chloroethyl ester obtained, which is now with phosgene with the addition of 5 g of dimethylformamide as a catalyst in 2-Chloräthanphosphonsäiiredichlorid is transferred. The reaction mixture already containing dimethylformamide as a catalyst is then used a bottom temperature of about 200 ° C and a pressure of about 4 (X) Torr distilled. Within

2 hours are obtained 249 g of a distillate, which 90% vinylphosphonic acid dichloride (82% of theory) and 9% 2-chloroethane phosphonic acid dichloride (8% the theory). Taking into account the recovered 2-chloroethane phosphonic acid dichloride is thus the yield from vinyl phosphonic acid dichloride 91% of theory, based on what is used Phosphorus trichloride.

Example 3

55g Phosphoiirichlorid are analogous to Example (I) reacted with 65 g of propylene oxide, the resulting THs- (2-chloropropyl) phosphite rearranged by heating to 170 ° C. for 5 hours. The obtained 2-chloropropane-di (2-eh! Orpropv!) - esier is converted into the dichloride with phosgene after adding 1 g of pyridine. The crude product thus obtained, the already contains pyridine as a catalyst, is now at a bottom temperature of about 2 (X) C and a Distilled pressure of approx. 4 (K) Torr. 47 g of propylene phosphonic acid dichloride are obtained within 50 minutes from Kp.y 77'-79 C, corresponding to 73% of the Theory, based on the phosphorus trichloride used.

Example 4

To 77Og methyl dichlorophosphine in 3.5 1 chlorobenzene 650 g of ethylene oxide are introduced with stirring and cooling at 20 to 25 C in the course of 3 hours. After stirring for one hour at 20-30 ° C., the resulting solution becomes in the course of 2 hours heated to 140 C under nitrogen and held at 130 140 C for 3 hours. After Abdesiillicren des Chlorhenzols under a little reduced pressure, 1356 g of almost colorless oil remain, which can be used without further purification in a cylindrical gassing vessel with a bottom filter after adding 5 g of triphenylphosphine oxide is gassed with phosgene at 130 '140 C until after

No more Diehlorälhan distilled off with the exhaust gases for 3 hours. 836 g of crude methane-2-chloroethylphosphinic acid chloride remain as a brownish oil. which already triphenylphosphino.xide as katal) salor and now in a distillation apparatus at a pressure of 4 (M) 500 Torr at 180 200 C. .Sump temperature is heated, with the resulting Hydrogen chloride distilled over a small amount of colorless oil. After heating for three hours the entire reaction mixture is distilled over by lowering the pressure. By fractional Distillation gives 585 g of methanevinyiphosphinic acid chloride therefrom and 70 g of higher-boiling fractions, the 85% methane-2-chloroilhylphosphine acid chloride retain. Including the recovered Melhan-2-chloroethylphosphinic acid chloride the yield of methanevinylphosphinic acid chloride is 75% of theory, based on the amount used Methyl dichlorophosphine.

Example 5

59 g of methyldichlorophosphine in 120 g of o-dichlorobenzene are mixed with 58 g of propylene oxide for 1 hour while stirring and cooling at 30.degree. The reaction mixture is heated to 170 ° C. over the course of half an hour and kept at this temperature for 2 hours. After removing the solvent. the residue is divided under reduced pressure

in addition of 1 g of triethylamine at about 150 ° C. with phosgene implemented. The crude mixture obtained, which already contains the triethylamine catalyst, is analogous Example (4) subject to cleavage. By fractional distillation under reduced pressure

\; from 58 g Methanpropeiiylphosphinsäurechlorid from Kp. erhallen ₂ 7 99 C, corresponding to a Ausheule of 84% of theory, based on Mcthyldiehlorphosphin.

- "B e i s ρ i e 1 6

320 g of crude, 85% strength benzene-2-chloroalhanophosphinic acid 2-chloroethyl ester. analogous to the previous examples by addition of ethylene oxide

2 ^r > benzene dichlorophosphine and thermal rearrangement; of the addition product was obtained, are reacted with phosgene at 135 145 C after the addition of 4 g of pyridine. The reaction product already containing the catalyst pyridine is at a

ίο bath temperature of 200 C under a pressure of Distilled 20 torr, leaving 60 g of resinous residue. The fractional distillation of the crude distillate results in 172 g of beiizolvinylphosphinic acid chloride of bp ,,, 94 95 C.

Example 7

550 g of Chloräthanphosphonsäuredichlorid were in a stirred vessel with thermometer and back flow cooler in the presence of
10 g of glycine heated with stirring.

The evolution of hydrogen chloride beginning at 150 ° C is finished after 2 '/: hours of heating to 180 ° C.

From the reaction mixture are distilled under a slowly increasing vacuum between 220 and 15 Torr = 29 26 <f- 1995 Pascal

ίο 430 g of colorless liquid distilled off, according to gas chromatography Analysis from 67% vinyl phosphonic acid dichloride and 32% chloroethane phosphonic acid dichloride consists. That corresponds to 87% d. Th. Of vinylphosphonic acid dichloride.

based on consumed 2-chloroethane phosphonic acid dichloride.

Claims (1)

Claim: Process for the catalytic production of acid chlorides containing vinyl groups Phosphorus of the general formula (I) R, OR ₁ \ II / C = CH-P