DE2951165A1 - 2-Phosphono-3-phosphoranylidene-succinate ester(s) - useful as intermediates and alkylating agents - Google Patents

Abstract

Esters of formula (I) are new. In (I) R1 and R2 are 1-8C alkoxy or aryl or together form a 5- or 6-membered ring; R3-R5 are 1-8C alkyl, 1-8C alkoxy or mono- or dialkylamino, or R3-R5 together form a 5- or 6-membered ring; R6 and R7 are 1-8C alkyl. (I) are esp. useful as intermediates for diphosphonosuccinic acid corrosion inhibitors and sequestering agents; (I) where at least one of R3-R5 is alkoxy are also useful as alkylating agents, e.g. for carboxylic acids.

Description

Phosphono-phosphoranylidenes and processes for their

Production The present invention relates to 1-phosphono-2-phosphoranylidene succinic acid esters of the general formula I. wherein R1, R2 independently of one another for a C1-C8-alkyl, C1-C8-alkoxy or for an aryl radical, where R1 and R2 can also together form a five- or six-membered ring, R3, R4, R5 independently of one another for one C1-C8-alkyl or C C1 8-alkoxy radical, or dialkylamino radical or alkylamino radical, where R3, R4, R5 can also jointly form five- or six-membered rings, R6, R7 independently of one another represent a C1-C8- Alkyl radical.

The invention also relates to a method for producing the 1-Phosphono-2-phosphoranylidene succinic acid ester of the general formula I and their use for the production of precipitation-inhibiting and corrosion-inhibiting 1,2-diphosphonosuccinic acids.

The process for the preparation of the 1-phosphono-2-phosphoranylidene succinic acid esters of the general formula I according to the invention consists in the reaction of phosphonomaleic acid esters of the general formula II, wherein R1, R2, R6, R7 have the same meaning as in formula I, with compounds of trivalent phosphorus of the general formula III, wherein R³, R4, R5 have the same meaning as in formula I.

Phosphonomaleic acid esters of the general formula II are known Substances.

Starting products for the phosphonomaleic acid esters used are 1-halophosphonosuccinic acid esters, which can be easily dehydrohalogenated. The 1-halophosphonosuccinic acid esters are in turn obtained by halogenation of phosphonosuccinic acid esters, which is a technically easily accessible and im represent base material produced on a larger scale.

It is also possible to use phosphonomaleic acid esters from acetylenedicarboxylic acid esters produced by the addition of dialkyl phosphites (cf. e.g. D.A. Nicholsen, Phosphorus 1973, 2, 143-146).

The naming of the following in the description of this invention 1,2-diphosphonosuccinic acid esters and phosphonomaleic acid esters mentioned as examples and the phosphono-phosphoranylidene has been made in such a way that the at the group P = O (phosphono group) bonded alkoxy or alkyl or aryl radicals of the Phosphono groups are placed in front as prefixes, whereby the OH groups are not expressly are mentioned, while the alcohols bound to the carboxy groups as esters are followed by the acid name.

Failure to mention substituents on the phosphono group therefore means the presence of the group -P03H2, the naming of only one substituent means that the second substituent is an OH group. This nomenclature is common (cf.Houben-Weyl, Methods of Organic Chemistry, Vol. XII, Part 1, pp. 10 and 11).

The substituents of the phosphoranylidene group are the same as usual Way prepended.

Suitable phosphonomaleic acid esters of the general formula II are e.g .: dimethoxyphosphonomaleic acid dimethyl ester diethoxyphosphonomaleic acid diethyl ester Di-n-butoxyphosphonomaleic acid di-n-butyl ester Di-i-butoxyphosphonomaleic acid di-i-butyl ester Di-sec-butoxyphosphonomaleic acid di-sec-butyl ester Di-2-ethylhexyloxyphosphonomaleic acid di-2-ethylhexyl ester Di-dodecyloxyphosphonomaleic acid di-dodecyl ester Diethoxyphosphonomaleic acid di-butyl ester Dimethoxyphosphonomaleic acid di-2-butoxyethyl ester Dimethoxyphosphonomaleic acid di-cyclohexyl ester Dimethoxyphosphonomals bis-triethylene glycol ester, bis-2-chloroethyl dimethoxyphosphonomaleic acid Bis-2-ethoxyethoxyphosphonomaleic acid dimethyl ester, methyl methoxyphosphonomaleic acid dimethyl ester Methyl ethoxyphosphonomaleic acid diethyl ester, ethyl methoxyphosphonomaleic acid dimethyl ester Phenyl methoxyphosphonomaleic acid dimethyl ester, 2-methyl-1-dimethoxyphosphonomaleic acid dimethyl ester Dimethylphosphonomaleic acid dimethyl ester or their mixed esters, as they are mostly spontaneously and voluntarily by transesterification from phosphonomaleic acid esters with different ones Form alkoxy radicals in Molektl.

Compounds of trivalent phosphorus of the general formula III are known in large numbers and include trialkyl phosphites, dialkyl aryl phosphites, Alkyldiarylphosphites, alkyl and arylphosphonous acid dialkyl esters, dialkyl and alkylarylphosphonous acid alkyl esters, Trialkylphosphines and mixed alkylarylphosphines.

The following representatives are listed as examples: trimethyl phosphite Triethyl phosphite tri-i-propyl phosphite tri-n-propyl phosphite tri-n-butyl phosphite tri-i-butyl phosphite Tri-pentyl phosphite Tris-2-ethylhexyl phosphite Tris-2-chloroethyl phosphite Dimethyl methanephosphonate Methanphosphonous diethyl ester Methanphosphonigsäuredi-n-butyl ester Ethanphosphonigsäurediethylester Dibutyl benzene phosphonate 2-chloroethanephosphonous dimethyl ester 4-methoxybenzene phosphonous di-butyl ester 4-Dimethylaminobenzolphosphonigsäuredimethylester Dimethylphosphinigsäurebutylester Dibutylphosphinous acid methyl ester Methyl-phenylphosphinous acid methyl ester 1-methoxy-1 -phosphacyclopentane 4-ethyl-2,6,7-trioxa-1-phosphabicyclo (2.2.2) octane 2-ethoxy-4-methyl-1,3,2-dioxaphosphacyclopentane Diethylphenyl phosphite, cyclohexylidene-1,4-bis-dimethyl phosphite, phenylene-1,3-bis-diethyl phosphite Mannitol-tris-ethylphosphite Pentaerythritol-bis-ethylphosphite Phosphorous acid-tris-dimethylamide Phosphorous acid diethyl ester dimethyl amide Phosphorous acid diethyl ester anilide Phosphorous acid dimethyl ester methyl amide Phosphorous acid ethyl ester bis-dimethylamide 2-methoxy-1,3,2-diazaphosphacyclopentane 2-dimethylamido-3-methyl-1,3,2-oxaazaphosphacyclopentane, 2-diethylamido-1,3,2-dioxaphosphacyclohexane Trimethylphosphine Tri-ethylphosphine tri-n-butylphosphine tricyclohexylphosphine triallylphosphine tris-2-cyanoethylphosphine 1-methylphospholane 1-methylphospholine diethylphenylphosphine methylethylphenylphosphine Phosphonomaleic acid esters of the general formula II and compounds of the trivalent Phosphorus of the general formula III are generally molar or approximately molar ratio 1: 1 used. If desired, a component in the Be used in excess. For substances that have more than one trivalent phosphorus atom per molecule can contain up to n mol of phosphonomaleic acid ester per mol of the compound are reacted with trivalent phosphorus, if n is the number of trivalent phosphorus atoms per molecule of the latter class of compounds. but Schüssige used reactants of the general formulas II or III can, if desired, be taken out of the Reaction mixture are removed.

It will mostly be advantageous to use the phosphonomaleic acid ester Formula II and the trivalent phosphorus compound of the formula to be reacted therewith III to be coordinated so that among the radicals R1 to R5 any alkoxy groups present are identical to one another and to the groups O-R6 and O-R7. Otherwise, in the course of further processing with transesterifications and possibly the release of alcohols as mixtures is to be expected. Basically, however the alkoxy radicals can be quite different and even mixtures of phosphonomaleic acid esters can be used and mixtures of compounds of trivalent phosphorus in those according to the invention Reaction can be used.

The process according to the invention can be carried out in the absence of a solvent or can be carried out in the presence of a solvent.

The implementation of the phosphonomaleic acid ester of the formula II with the Compounds of trivalent phosphorus of the formula III can be used in a wider temperature range from approx. -30 to approx. 1500C. A temperature range is preferred from -100C to 80 ° C.

The inventive method can be both continuous and be designed discontinuously. With the discontinuous procedure becomes either the phosphonomaleic acid ester or the compound of the trivalent Phosphorus optionally with one or more solvents or diluents submitted and the other reaction component, optionally with one or more Solvents tracked.

In general, the process of the invention is carried out under normal pressure carried out, but increased or reduced pressure can also be used.

An inert gas atmosphere is especially appropriate when light oxidizable compounds of trivalent phosphorus are used, suitable Inert gases are e.g. nitrogen and argon. Usually it is an inert gas atmosphere unnecessary.

The phosphono-phosphoranylidenes prepared by the process according to the invention are usually pure enough for their further use, if necessary one must Component of the general formulas II or III used in excess, e.g. by Evacuate at a sufficiently high temperature to be removed.

Phosphono-phosphoranylidenes are, provided they have at least one alkoxy group in the phosphoranylidene moiety, very good alkylating agents, e.g. for carboxylic acids. They can still be turned into using simple chemical methods convert corrosion-inhibiting and sequestering 1,2-diphosphonosuccinic acids, e.g. by partial or complete saponification, if necessary with the following Esterification or by alkyl halide-catalyzed rearrangement with subsequent Saponification.

The invention is illustrated by the following examples will: Example 1 280 g of dimethoxyphosphonomaleic acid dimethyl ester (1.11 mol) are presented. When trimethyl phosphite is added dropwise, an exothermic begins Reaction so that the reaction mixture can be kept at 45-500C by external cooling got to. A total of 138 g of trimethyl phosphite (1.11 mol) are added to the stirred, slowly the reaction mixture becoming more viscous was added dropwise. Then another hour kept at 500C and then all volatile impurities are at 1000C and deducted at a pressure of 2 mm Hg. The yield of non-volatile residue is practically quantitative and amounts to 417 g of 1-dimethoxyphosphono-2-trimethoxyphosphoranylidene succinic acid dimethyl ester.

Example 2 In the same way as the dimethoxyphosphonomaleic acid dimethyl ester in example 1 are shown in the examples compiled in the following table 2-20 other phosphonomaleic acid esters, characterized by the substituents R1, R2, R6, R7 with compounds of trivalent phosphorus, characterized by R³, R4, R5, implemented in Example 1 instead of the trimethyl phosphite. Make the products in all cases are viscous, clear liquids which are generally slightly yellowish are. A change in reaction temperature compared to Example 1 is shown in the table noted.

Example% No. R1 R2 R3 R4 R5 R6 R7 [° C] Yield 2 C2H3-O CH3-O O-C2H5 O-C2H5 O-C2H5 CH3 CH3 40 98 3 CH3-O CH3-O O-n-C3H7 CH3 O-n-C3H7 CH3 CH3 40 96 4 CH3-O CH3-O O-i-C4H9 O-i-C4H9 O-i-C4H9 CH3 CH3 50 97 5 CH3-O CH3-O O-i- / n- O-i- / n- O-i / n- CH3 CH3 50 97 C5H11 C5H11 C5H11 6 C2H5-O C25-O O-C2H5 O-C2H5 C2H5 C2H5 50 100 7 C2H5-O C2H5-O O-C2H5 O-C2H5 O-C2H5 CH3 CH3 40 98 8 CH3-O CH3-O O-C8H17 O-CH3 O-CH3 CH3 CH3 40 98 9 CH3 CH3-O O-CH3 O-CH3 O-CH3 CH3 CH3 70 99 10 C2H5 CH3-O O-CH3 O-CH3 O-CH3 CH3 CH3 70 96 11 C6H5 CH3-O O-CH3 O-CH3 O-CH3 CH3 CH3 50 97 12 CH3-O CH3-O N (CH3) 2 N (CH3) 2 N (CH3) 2 CH3 CH3 40 99 13 CH3-O CH3-O NH-CH3 O-CH3 O-CH3 CH3 CH3 40 99 14 CH3-O CH3-O CH2-CH2 - CH2-CH2 CH3 CH3 CH3 40 98 example % Entry R1 R2 R3 R4 R5 R6 R7 [%] Yield 15 CH3-O CH3-O O-CH2-CH2-O O-CH3 CH3 CH3 40 98 16 CH3-O CH3-O CH3 O-CH3 O-CH3 CH3 CH3 50 97 17 CH3-O CH3-O C4H9 C4H9 C4H9 CH3 CH3 80 97 18 CH3-O CH3-O O-C6H5 O-C2H5 CH3 CH3 40 19 CH3-O CH3-O O-C8H17 O-CH3 O-CH3 CH3 CH3 40 99 20 CH3-O CH3-O O-C2H4Cl O-C2H4Cl O-C2H4Cl CH3 CH3 40 96 example 21 252 g of dimethoxyphosphonomaleic acid dimethyl ester (1.0 mol) are mixed with 500 ml Submitted methylene chloride. When trimethyl phosphite is added dropwise, the heats up Solution and begins to boil. The heat of reaction is passed through a reflux condenser discharged. A total of 129 g of trimethyl phosphite (1.04 mol) are added dropwise. Afterward is stirred for a further 5 minutes and then the solvent is distilled off. the Residual solvent and excess trimethyl phosphite are at 1000C and at subtracted from a pressure of 3 mm Hg. The yield is 374 g of 1-dimethoxyphosphono-2-trimethoxyphosphoranylidene succinic acid dimethyl ester.

Example 22 126 g of dimethoxyphosphonomaleic acid dimethyl ester (0.5 mol) are mixed with 150 ml of toluene and cooled to -50C. The one when dripping heat generated by a total of 68 g of trimethyl phosphite (0.55 mol) is transferred to a cooling bath discharged so that a temperature of OOC can be maintained in the reaction mixture can.

The mixture is then kept cold for an hour and then to remove the solvent and the excess trimethyl phosphite used evacuated as in Example 21. The residue of 1-dimethoxyphosphono-2-trimethoxyphosphoranylidene succinic acid dimethyl ester weighs 183 g.

Example 23 252 g of dimethoxyphosphonomaleic acid dimethyl ester (1.0 mol) are presented with 200 ml of 1,2-propylene chloride. When trimethyl phosphite is added dropwise the solution warms up and begins to boil. The heat of reaction is over a Return flow sensor removed. A total of 129 g of trimethyl phosphite (1.04 mol) are added dropwise. The mixture is then stirred for a further 5 minutes and then the solvent is distilled off.

The residues will be solvent and excess trimethyl phosphite withdrawn at 1000C and at a pressure of 2 mm Hg. The yield is 376 g Dimethyl 1-dimethoxyphosphono-2-trimethoxyphosphoranylidene succinate.

Example 24 188 g of 1-dimethoxyphosphono-2-trimethoxyphosphoranylidene succinic acid dimethyl ester (0.5 mol) are added dropwise to 500 ml of 1N hydrochloric acid with stirring. The exothermic Reaction already heated aqueous solution is heated further to boiling and a methanol-water mixture is distilled off. To make up for the loss, the Water added to the reaction mixture from time to time. After 2 days, the reaction mixture becomes the water is drawn off in a water jet pump vacuum. The mostly frozen one Residue (141 g, equivalent weight: 46.8, theoretical equivalent weight for 1 , 2-Diphosphonosuccinic acid: 46.3) can be further purified by remelting to a crystalline pure product.

Example 25 278 g of diphosphonosuccinic acid (1.0 mol) are treated with a brought a significant excess of methanol at room temperature to the solution. This solution is then refluxed for 1 hour and then the excess, not The methanol which has reacted is stripped off in vacuo. Calculated from the weight gain methanol uptake of 2 moles per mole of diphosphonosuccinic acid used. The partial ester obtained solidifies at room temperature to form a glass-like, resin-like one Dimensions. The determination of the softening factor gives a value of 300.

Example 26 166 g of dimethyl 1-dimethoxyphosphono-2-trimethoxyphosphoranylidene succinate (0.422 mol) are heated to 1300C and mixed with 8 ml of methyl iodide. It takes place a strongly exothermic reaction, the temperature being reduced by appropriate cooling must be kept in the range 140-1500C. The rearrangement takes place after about 15 minutes completed and the reaction product can be purified by distillation (bp 3 mm Hg): 180-1900C).

The yield of 1-methyl-1,2-bis-dimethoxyphosphonosuccinic acid dimethyl ester is 146 g (88% of theory).

Example 27 146 g of the 1-methyl-1,2-bis-dimethoxyphosphonosuccinic acid dimethyl ester prepared in Example 26 will dissolved in 500 ml of water and treated with 10 ml of concentrated hydrochloric acid. Then it will be by continuously distilling off a methanol / water mixture at the same time Supply of water all the methanol bound in the ester from the reaction mixture removed. The saponification in boiling solution takes 18 hours.

After removing the water and the remaining hydrochloric acid in vacuo 1100C / 2 mm Hg gives 1-methyl-1,2-diphosphonosuccinic acid as one at room temperature Glass-like substance with a softening factor of 266.

Example 28 188 g of 1-dimethoxyphosphono-2-trimethoxyphosphoranylidene succinic acid dimethyl ester (0.5 mol) are presented.

To this, 30 g of glacial acetic acid (0.5 mol) are added dropwise with stirring, with the temperature of the reaction mixture is kept at 60 "C. After adding the acetic acid is held at 650C for a further few minutes. Methyl acetate is distilled off removed via a distillation bridge. The remaining methyl acetate is withdrawn at 1000C / 12 mm Hg from the mixture in a cooled template. The total yield of methyl acetate is 33 g (theory: 37 g), the residue of dimethyl 1,2-bis-dimethoxyphosphono-succinate weighs 182 g.

Claims (2)

Claims 1. 1-phosphono-2-phosphoranylidene succinic acid ester of the general formula wherein R¹, R2 independently of one another for a C1-C8-alkoxy or for an aryl radical, where R¹ and R² can also together form a five- or six-membered ring, 5 R3, R4, R5 independently of one another for a C1-C8-alkyl or C1 ~ 8-alkoxy radical, or dialkylamino radical or alkylamino radical, where R3, R41, R5 can also jointly form five- or six-membered rings, R61 R7 independently of one another represent a C1-C8-alkyl radical. 2. Process for the preparation of 1-phosphono-2-phosphoranylidene succinic acid ester according to Claim 1, characterized in that phosphonomaleic acid esters of the general formula are used wherein R1, R2, R6, R7 have the same meaning as in formula I, with compounds of trivalent phosphorus of the general formula in which R3, R41, R5 have the same meaning as in formula I, added.