IE42485B1 - Solution welding of plastics process for the preparation of phosphoric or phosphonic acid ester halides - Google Patents

Description

The pr.esent invention relates to a new process for the preparation of phosphoric and phosphonic acid ester-halides and to new phosphoric and phosphonic acid ester-halides obtainable with the aid of this process.

It is known to prepare phosphoric acid esterchlorides by selective reaction of phosphoryl chloride with alcohols (compare Houben-Weyl Xll/2, page 212 (1964)). The disadvantage of this process is that only a limited number of alcohols, especially primary alcohols, can be used as the starting material. Thus, the preparation of substituted compounds is correspondingly restricted and in certain cases, for example for phosphoric acid alkyl ester-halides halogenated in the 1-position in the alkyl radical, can be achieved in a controlled manner at best via a multi-stage reaction sequence.

A new process for the preparation Of phosphoric and phosphonic acid ester-halides has now been found which is characterised in that a compound of the general formula I R' .· Λ j .1/ x—P (I) . · R in which R represents an alkoxy radical with 1—8 carbon atoms, which is optionally substituted by halogen, and R’ represents a C.—CQ alkoxy radical, which is X o optionally substituted by halogen, or represents chlorine, bromine, fluorine or a C, alkyl or '1 6 phenyl radical, which is optionally substituted by halogen, and X represents fluorine, chlorine or bromine, is reacted simultaneously with a chlorinating or brominating agent and an olefine of the general formula ll R R \ / c = c 3^ A 5 R R (II) in which 4 R and R are identical or different and each represents hydrogen, halogen, a cyclohexenyl radical, or a straight-chain or branched optionally substituted —Clg alkyl, C —clg acyloxy or C2—C^2 alkenyl radical, (preferred optional substituents being halogen, acyloxy or alkoxy groups with 1—18 carbon atoms, the isocyanato group, the dichloroisocyano group,the chlorocarbonyl group, the cyano group, the chlorosulphonyl group, a carbalkoxy group with 1—8 carbon atoms in the alkoxy radical or an optionally substituted carb2 amoyl group with up to 12 carbon atoms), or R and r’ may also each represent a phenyl radical which is optionally substituted by halogen and/or 4 by alkyl group(s) and R also represents, in addition to the abovementioned groups, the - 4 chlorocarbonyl or cyano group or a carbalkoxy or optionally N-substituted carbamoyl radical, with, in each case, up to 9 carbon atoms, or represents an alkylcarbonyl, an alkylsulphonyl, an aryl5 carbonyl or an arylsulphonyl group with, in each case, up to 7 carbon atoms or represents a formyl or chlorosulphonyl group, or R2 and R^ are joined together to complete an optionally substituted 4membered to 12-meiribered, preferably 5-membered or 6-menibered, carbocyclic or heterocyclic ring, oxygen, sulphur or nitrogen preferably occurring as hetero-atoms, and R and R are identical or different and each represents hydrogen, halogen or a C,—Cr alkyl b radical, or a chlorocarbonyl, cyano, carbalkoxy or N-substituted carbamoyl radical, or R represents a phenyl radical.

Preferred compounds of general formula I are those in which R represents a —Cg alkoxy radical, preferably the methoxy and the ethoxy radical, and R* represents a alkoxy radical or represents a alkyl radical, chlorine, bromine, fluorine or the phenyl radical and preferably represents the methoxy, ethoxy, propoxy, isopropoxy, methoxy or ethyl radical and X represents chlorine.

Examples of compounds of general formula I are: phosphoric acid dimethyl ester-monochloride, phosphoric acid diethyl ester-monochloride, phosphoric acid diethyl ester-monobromide, phosphoric acid dimethyl ester-mono42485 - 5 fluoride, phosphoric acid dibutyl ester-monochloride, phosphoric acid monomethyl ester-dichloride, phosphoric acid monoethyl ester-dichloride, phosphoric acid monoethyl ester-difluoride, phosphoric acid mono-(2-chloroethyl) ester-dichloride, phosphoric acid monoisopropyl ester-dichloride, phosphoric acid monopropyl esterdichloride, methanephosphonic acid monomethyl esterchloride, ethanephosphonic acid monoethyl ester-chloride and phenyl-phosphonic acid monomethyl ester-chloride.

The compounds of general formula I which are used for the process according to the invention are known and can be prepared by reacting the corresponding acid chlorides such as, for example, phosphoryl chloride, with the appropriate alcohols (compare Houben-Weyl, Methoden der Organischen Chemie (Methods of Organic Chemistry) Volume XII, 2, page 211 (Stuttgart 1964J.

Preferred olefines of general formula II are those in which 4 R and R are identical or different and each represents hydrogen, fluorine, chlorine, bromine or an optionally substituted C^—acyloxy, C^—Cg alkyl or C„—Cr alkenyl radical, the optional £ o substituents being chlorine, bromine, the isocyanato group, the dichloroisocyano group, the chlorocarbonyl group, the cyano group, the chlorosulphonyl group, a carbalkoxy, acyloxy or alkoxy group with, in each case, up to 5, preferably up to 3, carbon atoms, or a carbamoyl group which is preferably substituted on the nitrogen atom by 2 methyl or ethyl, and R preferably represents 4 fluorine, chlorine or bromine and R has the abovementioned meanings except that it does not - 6 represent fluorine, chlorine or bromine 2 simultaneously with R .

Further preferred olefines are those in vzhich 4 R represents the ehlorocarbonyl group, the cyano group, a carbalkoxy or mono-or dialkylated carbamoyl group, with up to 5 carbon atoms, an alkylcarbonyl Or alkylsulphonyl group with up to 4 carbon atoms, or an arylcarbonyl or arylsulphonyl group, which preferably contains the phenyl radical 2 3 as the aryl radical, and preferably R , R and R5 are identical or different and each represents hydrogen, chlorine, bromine or a C—C„ alkyl 2 3^5° radical, at least one of R , R and R representing hydrogen.

Examples of olefines which are used for the process according to the invention are: branched and unbranched alkenea, especially ethylene, propylene, but-l-ene and but 2-ene, isobutene, hex-l-ene, dodec-l-ene, tri- and tetrapropylene, tetraisobutene, oct-I-ene, octadec-l-ene, 1phenyl-3,3,4,4-tetrafluorocyclobutene, cyclopentene, cyclohexene, cyclooctene, cyclododecene, styrene, amethylstyrene and α-pinene? diolefines, especially buta1,3-diene, isoprene, 2,3 - dimethyl - buta - 1,3 - diene, vinylcyislohexene and cycloocta - 1,4 - diene; halogenated olefines, such as allyl chloride, methallyl chloride and vinyl chloride, 1- and 2-chloropropene, 1,4- and 3,4dichloro - but - 2 - ene, vinyl bromide and allyl bromide, vinyl fluoride, 1,1 - dichloroethylene, 1,1difluoroethylene and trifluoromonochloroethylene, 1chloro - cyclohexene and 3 - chloro - cyclohexene; esters, mono- and dialkylamides, chlorides and nitriles 43485 - 7 of unsaturated carboxylic acids, especially of acrylic acid, methacrylic acid, crotonic acid, β,β - dimethylacrylic acid, β - chloroacrylic acid, β,β - dichloroacrylic acid, vinylacetic acid, undecenecarboxylic acid, oleic acid, linoleic acid, cyclohexene - 1 - carboxylic acid and cyclohexene - 3 - carboxylic acid, maleic acid, itaconic acid and fumaric acid; esters and ethers of unsaturated alcohols, especially of allyl alcohol, but2 - ene - 1,4 - diol and 1,3 - dioxolene - 2- ene ; isocyanates and isocyanide - dichlorides with olefinic groupings, especially allyl isocyanate and allyl isocyanide-dichloride, 4 - chloro - but - 2 - enyl isocyanate and 4-chlorobut - 2 - enyl isoeyanide-dichloride; ketones and sulphones with olefinic groupings, especially methyl vinyl ketone, mesityl oxide, phenyIvinylsulphone, 3-sulpholene and 3-methy1-3-sulpholene; and olefinic sulphonic acid derivatives, especially β-chloro-vinyl-, allyl- and methylallyl-, vinyl- and β,β-dimethylvinylsulphonyl chloride.

Very particularly preferred olefines are those according to the general formula II in which 2 3 R and/or R represent fluorine, chlorine, or bromine, especially fluorine or chlorine, and R also can represent hydrogen and 4 5 the radicals R and R in each case represent hydrogen or a —σθ alkyl radical or the phenyl radical.

Examples which may be mentioned are: monofluoroethylene, monochloroethylene, monobromoethylene, 1,1-difluoroethylene, 1,1-dichloroethylene, l-fluoro-2-methylethylene, 1-fluoro-2-ethylethylene, l-fluoro-2-phenylefchylene,1-chloro-prop-l-ene and 2-chloro-prop-1-ene. - 8 10 The vinyl fluorides and vinylidene fluorides which are employed for the process according to the invention are known or can be prepared according to known processes, for example by an addition reaction of one molecule of HF with appropriate acetylenes or, respectively, of two molecules of HF with acetylene, subsequent chlorination and dehydrochlorination.

The phosphoric and phosphonic acid ester-halides obtainable by 'the process according to the invention are defined as being these which can be represented by the general formula III R II z „2 «4 R R '3 '5 R R (III) in which R has the same meaning as R‘ for material of the general formula I a radical of the formula the starting or represents R , R , R , R and X have the same meanings as for the starting materials of the general formula II and Y represents chlorine or bromine, in accordance with the halogenating agent used for the process according to the invention. - 9 Examples of phosphoric and phosphonic acid esterhalides. according to the general formula III, are those having the symbol meanings set forth in Table I.

TABLE 1 X Y R R2 R3 R4 R5 Cl Cl Cl Cl H H H ci Cl Cl Br H H H Cl ClCIi3 Cl H H H Cl Cl och3 Cl H H H Cl Cl oc2h5 Cl H H H Cl BrOC3H7 Cl H H H Cl Cl Cl ch3 HCH3 H Cl Br OCH3 ch2ci H K H Cl Cl Cl -CH=CH2 H H H Cl Cl oc3h7CA 6 5 H H H New compounds, which are obtainable with the aid of the process according to the invention, are those of the general formula III, in which X represents fluorine, chlorine or bromine, Y represents chlorine or bromine, R represents a C.—C. alkyl radical optionally 4 ° 2 3 4 5 substituted by halogen, and R , R , R and R are as previously defined; and also compounds of the general formula III, in which X represents fluorine, chlorine or bromine, Y represents chlorine or bromine.

R represents a C.—Co alkoxy radical, which is 1 8 optionally substituted by halogen, or represents 424Q» - ίο fluorine, chlorine or bromine, R2 represents fluorine, 4 5 R represents fluorine or hydrogen and R and R (which may be the same or different) each repre5 sents hydrogen, alkyl or phenyl.

Hie compounds of general formula III having the symbol meanings listed in Table 2 may be mentioned by way of example: TABLE 2 X Y R R2 R3 R4 R5 F ClCIi3° F F H H Cl Cl CHjO F F H H Cl Br CH,0 F F H H Cl Cl ch3° F H H H Cl ClC2?5O F H H H Cl Cl Cl F £* H H Cl Br Cl F F H a Cl Cl Cl F H H B Cl Br Cl F H H H F Cl F F H H H Br Cl Br F H H H Elementary chlorine or bromine can be used as the halogenating agent for the process according to the invention. Of course, compounds which split off chlorine or bromine under the reaction conditions, for example sulphuryl chloride, can also be employed.

The reaction temperature for the reaction according to the process of the invention is not in itself critical and can vary within wide limits, in general, the reaction is carried out at from -50 to +120°c. - 11 appropriately from -10 to +1OO°C and preferably at -10 to +50°C.

In general, the reaction is carried out under normal pressure.

The process according to the invention is preferably carried out in the presence of solvents or diluents. Solvents and diluents which can be used are organic solvents which are inert towards the reactants, such as, for example, aliphatic and aromatic chlorinated hydrocarbons, dichloromethane, chloroform, chlorobenzene or dichlorobenzene but also an excess of the reactant of general formula I, in so far as this is liquid under the reaction conditions.

In some cases it has also proved advantageous to add a small amount of Friedel-Crafts catalysts, especially, for example, iron-(III) chloride, zinc chloride or aluminium chloride, to the reaction mixture. in order to achieve good yields, the process according to the invention is appropriately carried out using equivalent amounts of halogenating agent and at least equivalent amounts of the reactant of general formula I, these amounts being based on the olefine. In general, particularly good results are obtained when the reactant of general formula I is used in excess, for example in a molar ratio of 1:1 to 5:1, based on olefine employed.

Using, as an example, the reaction of phosphoric acid monomethyl ester-dichloride with vinyl chloride as the olefine and chlorine as the halogenating agent, the process according to the invention can be illustrated in more detail by the equation which follows: - 12 4248 5 Cl It / Cl - Ρ + CH = CH-C1 + Cl, \ 2 °-ch3 Cl II z -> Cl - P + CH,C1 \ 3 OCH-CH -Cl I 2 Cl When the phosphoric acid ester used as the starting material contains two alkoxy groups as the substituents R and R1, the reaction according to the process of the invention can be continued stepwise, when an appropriate excess of olefine and halogenating agents are present, by substitution of both alkoxy groups to give two new phosphoric acid diestermonohalides, as is illustrated in more detail by the equa10 tion which follows, using, as an example, the reaction of phosphoric acid dimethyl ester-monochloride with vinyl fluoride as the olefine and chlorine as the halogenating agent: OCH II z 3 Cl-P \ och3 C12,CH2=CHP -CHjCl * C12,CH2=CHF -CIJ3C1 OCH.

II z 3 Cl-P \ O-CHF CH_C1 I 2 O .O-CHF «/ Cl-P \ O-CHF ch2ci - 13 In this case the phosphoric acid ester-halide obtainable as the product contains, in place of the radical R', the radical R2 R4 I I -0 - C - C - Y R3 R5 R R In order to carry out the process according to the invention in practice it is appropriate initially to introduce the reactant of general formula I,if necessary in an inert solvent or diluent, and to add the halogenating agent and the olefine simultaneously to this solution at the indicated temperatures, the internal temperature of the mixture being regulated by external cooling. After the reaction has subsided, the batch is stirred for a further period whilst warming (preferably at 40 to 1OO°C) in order to carry the reac tion to completion. The reaction mixture is then cooled to room temperature and worked up according to customary methods, for example by fractional vacuum distillation.

The products obtainable according to the process of the invention are generally obtained in the form of colourless to pale yellow coloured oils, which are insoluble in waiter and which generally can be distilled without decofoposition under reduced pressure and can be purified in this way. When mixtures of different isomers are obtained as the product, these can be separated by fractional distillation.

An advantage of the process according to the invention is that the preparation of known phosphoric acid ester-halides is considerably simplified and 43485 - 14 numerous new compounds of this type, which cannot be prepared according to methods known hitherto, are accessible.

A further advantage is that the process according to the invention has universal applicability and can be carried out industrially in a simple manner and that the requisite starting materials are readily accessible. The high purity and good yields of the products obtain able by the process according to the invention is also advantageous.

The phosphoric acid ester-halides which can be prepared according to the process of the invention serve as intermediate products for the preparation of insecticides and flameproofing agents (compare U.S. Patent Specification 2,947,773/Table 1).

Example 1. g of vinyl fluoride and 70 g of chlorine are simultaneously passed into 308 g of phosphoric acid di methyl ester-monochloride (CH^O) 2POC1 at -5°C to 0°C, whilst stirring and cooling. After the reaction has taken place, the mixture is first degassed in vacuo at room temperature and then is subjected to fractional distillation. 143 g (=69% of theory) of phosphoric acid 0-methyl-0-(2-chloro-l-fluoroethyl) ester-monochloride of the formula Cl—PO ( och3 ). (OCHP—ch2c 1) which has a boiling range b.p.Q 3: 69°—72°C, and 11 g (=8% of theory) of phosphoric acid di(2-ehloro-l-fluoroethyl) ester-monochloride of the formula Cl—PO (0CHE—CH2Cl) 2 424S5 - 15 which has a boiling range b.p.Q 85°—90°C, are obtained.

Example 2.

The reaction is carried out analogously to Example 5 1, using 600 g of (CH^OjPOCl, 195 g of Cl^ and 140 g of vinyl fluoride, instead of the amounts indicated in Example 1. In this case 307 g (52% of theory) of the compound Cl—po(och3) (OCHF—ch2—Cl) and 72 g (=21.5%) of the compound Cl—PO (OCHF—CH2 Cl) 2 are obtained.

Example 3. g of chlorine and 90 g of vinyl chloride are 15 passed into 172 g of phosphoric acid diethyl ester-monochloride Cl—PO(OC2H5)2· The temperature is kept at about 0°C by cooling. The reaction mixture is warmed to 50°C in order to remove ethyl chloride and is then sub · jected to fractional distillation in vacuo. 105 g (=43.5% of theory) of phosphoric acid 0-ethyl-0-(1,2dichloroethyl) ester-monochloride of the formula Cl—P0(0C2H5)(0CHC1—CH2C1), which has a boiling point b.p.Q 72°C, and 52 g (=33.4% of theory) of phosphoric acid di-(1,2-dichloro25 ethyl) ester-monochloride Cl—po(ochc1—ch2ci)2, which has a boiling point b.p.Q 11O°C, are obtained. - 16 Example 4. g of vinyl fluoride are passed into 212 g of Cl—POiOCHg^ at about 0°C, whilst stirring and cooling, 117 g of bromine being added dropwise at the same time.

The mixture is then degassed under a waterpump vacuum and subjected to fractional distillation. 120 g (=65% of theory) of phosphoric acid 0-methyl-0-(2bromo-l-fluoroethyl) ester-monochloride of the formula Cl—PO(OCH3) (OCHP—CH2Br) , which has a boiling range b.p. : 80°—83°C, and 14 g U· L of the compound Cl—PO(OCHF—CH2Br)2, Which has a boiling range of 100°—105°/0.15 mm Hg, are obtained.

Example 5. g qf chlorine and 20 g of vinyl fluoride are passed into 20 g of phosphoric acid monopropyl esterdichloride Cl2PO—0—nC3H? at -10°G to 0°C. 20.2 g (=85% of theory, based on phosphoric acid propyl ester20 dichloride employed) of phosphoric acid (2-chloro-lfluorethyl) ester-dichloride of the formula Cl2PO—OCHP—ch2ci, which has a boiling range of 46°—48°c/0.2 mm Hg, are obtained by fractional distillation.

Example 6. g of vinyl fluoride and 40 g of chlorine are passed into 80 g of phosphoric acid monoethyl ester-dichlo ride at about 0°C. After working up by fractional distillation, 75 g (=77.5% of theory, based on phosphoric 3485 - 17 acid ethyl ester-dichloride employed) of the compound C12PO—0—OHF—CH2C1, which has a boiling range of 43°— 46°c/0.1 mm Hg, are obtained.

Example 7. g of vinyl chloride and 20 g of chlorine are passed into 20 g of phosphoric acid monopropyl esterdichloride, the reaction temperature being kept between 0°C and +10°C by cooling. Working up by distillation gives 16 g (=62.5% of theory) of phosphoric acid (1,2dichloroethyl) ester-dichloride, which has a boiling range of 56°—60°c/0.1 mm Hg.

Example 8. g. of vinyl bromide are added dropwise to 80 g of phosphoric acid monoethyl ester-dichloride at -5°C to 0°C, 45 g of chlorine being passed in simultaneously and the heat of reaction being compensated by a cooling bath. 52 g (=40% of theory) of the compound CH2Cl—CHBr—0—POC12, which has a boiling range of 66°—68°C/O.1 mm Hg, are obtained by fractional distillation of the resulting product mixture.

Example 9. 100 g of chlorine and 65 g of vinyl fluoride are simultaneously introduced into 135 g of ethanephosphonic acid ethyl ester chloride. The temperature is kept at between -10°C and 0°C by means of cooling. After working up by fractional distillation, 120 g (=67% of the theory) of ethanephosphonic acid (2-chloro-l-fluoroethyl ester) chloride, which has a boiling range of 65—67°C/0.2 mm Hg, are obtained. - 18 43485 Example 10. g of chlorine, 39 g of vinylidene fluoride and in addition 0.5 g of FeCl^ are introduced into 67 g of phosphoric acid methyl ester dichloride. The temperature is kept at 10 to 20°C by means of booling. After working up by fractional distillation in vacuo, 75 g (75% of the theory) of phosphoric acid (2-chloro1,1-difluoro-ethyl ester)-dichloride, which has a boil ing range of 45—5O°C/4 mm Hg, are obtained.

Claims (18)

1. CIAIMS:1. A process for the preparation of a phosphoric or phosphonic acid ester-halide as hereinbefore defined, characterised in that a compound of the general formula I II z 0 R' (I) in which R represents an alkoxy radical with 1—6 carbon atoms, optionally substituted by halogen, and R* represents a —οθ alkoxy radical, optionally substituted by halogen, or represents chlorine, bromine, fluorine or a —Cg alkyl or phenyl radical, either of which is optionally substituted by halogen, and X represents fluorine, chlorine or bromine, is reacted simultaneously with a chlorinating or brominating agent and an olefine of the general formula II R' R' ,5 (II) in which 2. 3 R represents fluorine, R represents fluorine or 2 . 3 wherein R represents fluorine, chlorine or bromine, R represents fluorine, chlorine, bromine, or hydrogen and 2 3 5 lo at least one of R , R and R representing hydrogen. 2 4 R represents fluorine, chlorine or bromine and R is as defined in claim 4, but does not represent fluorine, chlorine or bromine.

2. A process according to claim 1, wherein R represents a C^-Cg alkoxy radical, R represents a C^-C^ alkoxy radical, a chlorine, fluorine or bromine atom, a C^-C^ alkyl radical or a phenyl radical, and X represents chlorine. 2 4 R and R are identical or different and each represents hydrogen, halogen or a straight-chain or branched optionally substituted alkyl, C,—C acyloxy or C_—C,_ alkenyl radical, a X lb Ζ 1Z cyclohexenyl radical, or a phenyl radical which is - 20 424S5 optionally substituted by halogen and/or by C^-C^ alkyl group(s) and R may, in addition, represent a chlorocarbonyl, or a cyano group, a carbalkoxy or an optionally N-substituted carbamoyl radical containing in each case, up to 9 carbon atoms, an alkylcarbonyl, alkylsulphonyl, arylcarbonyl or arylsulphonyl group containing, in each case, up to 7 carbon atoms or a formyl or chloro2 4 sulphonyl group, or the radicals R and R are joined together to complete an optionally substituted 4-membered to 12-membered, carbocyclic or heterocyclic ring, and 3 5 R and R are identical or different and each represents hydrogen, halogen or a C^-Cg alkyl radical or a chlorocarbonyl, cyano, carbalkoxy or N-substituted carbamoyl radical, or r5 represents a phenyl radical. 3. °

3. A process according to claim 1 or claim 2, wherein R 2 or R^ represents a c i _c ^g alkyl, C^-C^g acyloxy or alkenyl radical substituted by a halogen atom, by an acyloxy or alkoxy group containing from 1 to 18 carbon atoms, an isocyanato, dichloroisocyano, chlorocarbonyl, cyano or chlorosulphonyl group, a carbalkoxy grohp containing from 1 to 8 carbon atoms in the alkoxy moiety or an optionally-substituted carbamoyl group containing up to 12 carbon atoms. 4. 5 hydrogen and R and R each represents hydrogen, 4 5 25 R and R each represent hydrogen, or a C^—C g alkyl radical or phenyl.

4. A process according to claim 1 or 2, wherein - 21 2 4 R and R are identical or different and each represents hydrogen, fluorine, chlorine, bromine, an optionally substituted C.—C_ acyloxy, C,—C,. alkyl or C„—C. X □ lb zb alkenyl radical, the optional substituents in each case 5 being chlorine, bromine, isocyanato, dichloroisocyano, chlorocarbonyl, cyano, a carbalkoxy, acyloxy or alkoxy group containing, in each case, up to 5 carbon atoms, or a carbamoyl group optionally N-substituted by a methyl or ethyl group.

5. Y represents chlorine or bromine, R represents a C.—C alkoxy radical, which is optionally substituted X 8 by halogen, or represents fluorine, chlorine or bromine, 5 catalyst. 5 carbon atoms, or an alkylcarbonyl or alkylsulphonyl 2 3 group containing up to 4 carbon atoms, and R , R and R are identical or different and each represents 20 hydrogen, chlorine, bromine or a C—alkyl radical,

6. A process according to claim 1 or 2, wherein

7. A process according to claim 1, 2, 4 or 5

8. A process according to any one of claims 1 to 7, wherein the chlorinating or brominating agent is elementary chlorine or bromine.

9. A process according to any one of claims 1 to 8, wherein the reaction is effected at a temperature 434S S - 22 of from -50 to +120°C. 10. C^—C 4 alkyl or phenyl. 10 described in any one of Examples 1 to 8.

10. A process according to any one of claims 1 to 9, wherein the reaction is carried out in the presence of an organic solvent or diluent and a Friedel-Crafts 10 5. A process according to claim 1, 2 or 4, wherein

11. A process according to claim 1, substantially as hereinbefore described.

12. A process for the preparation of a phosphoric or phosphonic acid ester-chloride substantially as

13. A phosphoric or phosphonic acid ester-chloride prepared by a process according to any one of claims 1 to 12.

14. A process for the preparation of a phosphoric 15 or phosphonic acid ester-chloride substantially as described in Example 9 or 10.

15. A phosphoric or phosphonic acid ester-chloride prepared by a process according to claim 14. 15 R represents chlorocarbonyl, cyano, a carbalkoxy, or mono- or di-alkylated carbamoyl group containing up to

16. A compound of the general formula 0 R. in which X represents fluorine, chlorine or bromine, Y represents chlorine or bromine, R represents a alkyl radical optionally 48485 - 23 2 3 4 5 substituted by halogen, and R , R , R and R are as defined in any one of claims 1 to 7.

17. A compound of the formula given in claim 16, wherein X represents fluorine, chlorine or bromine,

18. A compound according to claim 17 described in Example 10.