3,409,707 United States Patent Office Patented Nov. 5, 1968 1. 2 The following is a typical embodiment of equation 3,409,707 (C), above: DI THO PHOSPHORUS PHOSPHONIUMSALTS Martin Grayson, Norwalk, Patricia Tarpey Keough, Ridge 69 g 6 Na2CO3 e) 6 field, and Michael McKay Rauhut, Norwalk, Conn, as (CH3)3P CHCH, OCCH.Cl -> (CH3)3P CH=CH-Cl signors to American Cyanamid Company, Stamford, More specifically, in generic Equations A, B and C, Conn., a corporation of Maine No Drawing. Application Feb. 12, 1964, Ser. No. 344,224, above, R, R2 and R3 each represent alkyl C1-C1s, sub now Patent No. 3,299,143, dated Jan. 17, 1967, which stituted alkyl C1-C1, cycloalkyl, and aryl; X represents is a continuation of application Ser. No. 256,124, Feb. 4, halogen, such as bromo, chloro and iodo, and tetraphenyl 1963. Divided and this application Oct. 30, 1964, Ser. borate; and Y in Equations B and C represents the res No. 407,873 0 idue of an acylating agent as shown in the specific em 4 Claims. (C. 260-931) bodiments, supra. Typical tertiary reactants are the following: trimethylphosphine, tirethylphosphine, tripropylphos phine, tributylphosphine, tripentylphosphine, trihexyl ABSTRACT OF THE DISCLOSURE 5 phosphine, triheptylphosphine, trioctylphosphine, tri Phosphonium salt derivatives of the formula onylphosphine, tridecylphosphine, triundecylphosphine, S A tridodecylphosphine, tritridecylphosphine, tritetradecyl phosphine, tripentadecylphosphine, trihexadecylphos phine, dodecyldiethylphosphine, dioctylpropylphosphine, unreleakA. se 20 diethylbutylphosphine, butylethylhexylphosphine, tri(2- wherein R, R2, R, A, A and X are as hereinafter de methoxypentyl) phosphine, tris - 2 - cyanoethylphos fined. The compounds are useful as fire retardants in phine, diethyl - 2 - ethoxyheptylphosphine, tricyclo plastics. propylphosphine, tricyclohexylphosphine, triphenylphos phine, diphenylnaphthylphosphine, trixylylphosphine, tri 25 tolylphosphine, tris(para - ethoxyphenyl)phosphine, tris The instant application is a division of U.S. applica (para - chlorophenyl)phosphine, tris(2 - chlorophenyl) tion Ser. No. 344,224, filled Feb. 12, 1964, now U.S. phosphine, tris(3 - bromophenyl)phosphine, and the like. Patent 3,299,143, issued Jan. 17, 1967, which in turn was Typical esterifying agents follow: lower alkanoic a continuation of U.S. application Ser. No. 256,124 filed 30 anhydrides, such as acetic anhydride, propionic anhy Feb. 4, 1963, now abandoned. dride, butanoic anhydride; lower alkanoic acids, such as The present invention relates to organophosphorus com formic acid, acetic acid, propionic acid, butanoic acid; pounds and to a method of preparing same. More par acylating (C-C8 alkanoyl) halides, such as acetyl ticularly, the instant discovery concerns phosphonium chloride, propionyl bromide, butyryl iodide, octanoyl salt derivatives of tertiary . chloride, dodecanoyl bromide, stearyl chloride, hexanoyl It has been found that tertiary phosphines generally bromide; isopropenyl acetate; aryl sulfonyl halides, such will react with halo-substituted ethanol to produce the as para - toluenesulfonyl chloride, phenyl sulfonyl bro corresponding trialkyl-, tricycloalkyl-, or tri-aryl-2-hy mide, 2,4 - dimethylphenylsulfonyl chloride; alkyl droxyethylphosphonium salts. In turn, these salts may be (lower) chloroformates, such as ethylchloroformate, acylated using a lower alkanoic anhydride, lower 40 butylchloroformate; alkyl (lower) carbonates, such as alkanoic acid, or the like, to produce their correspond diethylcarbonate, dipropylcarbonate, dibutylcarbonate; ing trialkyl-, tricycloalkyl, or triary1 - 2 - acetoxyethyl ketene; dimethyl sulfate; nitrosyl chloride; and trimethyl phosphonium salts. phosphate. The following equations illustrate this general reac In Equation C, above, typical suitable inorganic and organic bases are: alkali metal hydroxides, such as so tion: 45 dium hydroxide, , lithium hydroxide; (A) RR2R3P -- XCHCH-OH - RRR-FCHCH,0Hs€9 alkali metal carbonates, such as sodium carbonate, potas sium carbonate, lithium carbonate; alkaline earth metal (B) esterifying agent hydroxides, such as magnesium hydroxide, barium hy R1,R2R3P CHCHOH.X ------> 50 droxide, calcium hydroxide; alkaline earth metal carbon ates, such as magnesium carbonate, barium carbonate, calcium carbonate; activated alumina; and quaternary am R, R2, R3 each representing, as will be seen hereinafter, monium hydroxides, such as tetraalkyl (lower) ammo alkyl, cycloalkyl and aryl, nium hydroxides, including tetramethylammonium hy X representing halogen or tetraphenyl borate, and Y rep droxide, tetrapropylammonium hydroxide, and tetraben resenting the residue of an acylating or esterifying 55 Zylammonium hydroxide; and basic ion exchange resins. agent. The following is a typical embodiment of generic The reaction in Equation A hereinabove is carried out Equations A and B, above: at a temperature in the range of 30° C. to 250° C., pref erably 60° C. to 180° C. The Equation Breaction. above, 60 is best carried out at a temperature in the range of 5 C. to 150 C. As to Equation C, above, this reaction is gen erally carried out at a temperature in the range of 20° C. O to 180° C., preferably 50° C. to 150° C. Each of these three reactions may be carried out at 65 atmospheric, sub-atmospheric or super-atmospheric pres The trialkyl-, tricycloalkyl-, and triary1 - 2 - acetoxy Sure; preferably, however, reaction is carried out at atmos ethylphosphonium salts prepared as above may, in turn, pheric pressure. By the same token, the ratio of the re be converted to their corresponding vinylphosphonium actants in each of Equations A, B and C is not critical, an salts according to the following general equation: excess of either reactant, in each equation, with respect (C) 6 G base €E) 6 70 R1R2R3P CHCHOY,X - R1R2R3P CH-scCHX Typical are:polymeric quarternary ammonium salts, e.g., in which R, R2, R3, Y and X are the same as above. polymeric trimethylbenzyl ammonium chloride, etc. 3 3,409,707 4. to the other being suitable. In Equation B, however, an moles), and tributylphosphine (204 grams, 1.01 moles) excess of about 10% by weight of the acylating agent rela are combined under nitrogen and refluxed at 85 C. tive to the phosphonium salt reactant is preferred. Gen overnight with stirring. A heavy oil forms within an hour. erally in Equations A and C stoichiometric amounts of Isopropenyl acetate (320 grams, 3.2 moles) and 48% the reactants are employed. 5 HBr (3 drops) are slowly added to the reaction mixture The reactions of Equation A, above, are best carried which is then refluxed 18 hours. Volatile components out in the presence of an inert organic solvent, i.e., a are removed in vacuo at 70° C. Product (372.5 grams; solvent which does not enter into or otherwise interfere 99.9% yield) remains as a thick hygroscopic oil, which with the reaction under the conditions contemplated here could be forced to crystallize by stirring in a benzene in. Typical solvents are dimethoxyethane, dioxane, ethyl petroleum ether. (boiling point 30° C.-60 C.) mixture. acetate, tetrahydrofuran, and the like. 10 Crystalline tributyl-2-acetoxyethylphosphonium salt is The reactions of Equation B similarly are best carried obtained from part of the oily product by freeze drying out in the presence of an inert organic solvent of the type a benzene solution of the oil...... described for Equation A, as well as acetic acid, dimethyl Example III-Tributyl-2-acetoxyethylphosphonium formamide, diglyme, and the like. . . " tetraphenylborate As to Equation C, typical suitable inert organic Solvents in which the phosphonium salt is solvent, which solvents Tributyl-2-acetoxyethylphosphonium bromide oil (16.2 do not interfere or enter into reaction to any substantial grams produced as in Example II, above) is dissolved degree, are dimethoxyethane, dioxane, dimethylformam in water and treated with sodium tetraphenylboror ide, diglyme, acetonitrile, ethylacetate, tetrahydrofuran, 20 (15 grams) dissolved in water. A white precipitate ap and other like linear and cyclic ethers, acetate esters pears which is filtered and recrystallized from ethanol (lower alkyl). containing enough acetonitrile to cause solution at the Alternatively, it has been found pursuant to the instant boiling point of the mixture. Tributyl-2-acetoxyethyl discovery that the products of Equation A, above, may phosphonium tetraphenylborate (16.7 grams) is obtained be converted directly to the products of Equation C, 25 with melting point of 177 C-179 C. Analysis of prod thusly, D uct (Found: C, 76.65; H, 8.83; P, 5.24. C40H5O2BP requires: C, 78.93; H, 8.94; P, 5.10%.) Example IV.- Triphenyl-2-acetoxyethylphosphonium iodide in the presence of any base given above for Equation C 30 and at a temperature in the range of 100 C. to 250 C. 2-iodoethylacetate is prepared from the nucleophilic As in Equation C, a solvent of the type given hereinabove exchange reaction of sodium iodide and 2-chloroethyl for Equation C is suitable and herein contemplated. If acetate in refluxing acetone under nitrogen (boiling point desired, the reaction may be carried out in the presence 86° C.-90° C. at 33 milliliters mercury). Triphenyl of a dehydrating agent, such as a siliceous agent includ 35 phosphine (7.35 grams) is reacted with 2-iodoethyl ing silica (e.g. silica gel), silica-alumina, and the like, in acetate (24 grams) under nitrogen with stirring at 80 which other inert organic solvents are also suitable, e.g. C. for 4.5 hours. The excess 2-iodoethylacetate is aromatic hydrocarbons, such as toluene, benzene, Xylene, distilled off in vacuo. Crude, brown crystalline product cymene, and the like, methylene chloride, ethylene chlo (14.20 grams) is obtained by washing oily residue with ride, etc. . 40 ether. It is washed with ether, ethylacetate, and acetone The products of Equations A, B, C and D above are and recrystallized from acetonitrile to give product (7.90 useful as fire retardants in plastics, e.g., from 0.5 to 30 grams) with melting point 161 C-163. C. Analysis of parts by weight of any one of above compounds when product (Found: C, 55.16; H, 4.80; I, 26.77; P, 6.45. incorporated into 100 parts by weight of a thermoplastic CHOIP requires: C, 55.47; H, 4.66; I, 26.66; P, polymer material, such as polyethylene, polypropylene, 6.51%.) . . . . polystyrene, polyacrylate, polymethylmethacrylate, or the Example IV represents still another embodiment of like, provides enhanced fire retardance to the polymer ma the present invention wherein the product. Salts of terial upon exposure to an open flame. Equation B, above, are prepared directly from the re While the following examples specify certain details action of a 2-haloethyl acetate with a tertiary phosphine of the type contemplated herein. ------as to certain embodiments of the present invention, it is The process of Example IV, above, may be carried not intended that these details impose unnecessary limita out using any of the tertiary phosphine reactants con tions upon the scope of the instant discovery, excepting of templated herein and the corresponding tri-substituted course that these limitations appear in the appended 2-acetoxyethylphosphonium halide produced and re claims: covered, according to the following equation Example I.-Tributyl-2-hydroxyethylphosphonium 5 5 tetraphenylborate (E) O RR2R3P -- XCHCHot-CH, - R1R2R3P€e CHCHOY-X6) Tributyl-2-hydroxyethylphosphonium bromide, ob wherein R, R2, R3, X and Y have the meanings given tained from combining tributylphosphine and 2-bromo hereinabove in Equations A and B. , ethanol in 1,2-dimethoxyethane and refluxing under nitro 60 Equation E is best carried out at a temperature in gen, is dissolved in water and treated with excess 0.1 N the range of 5 C. to 150° C., preferably at the reflux sodium tetraphenylboron. The resulting precipitate is fil temperature of the solvent employed. Typical linert tered and recrystallized from ethanol to yield product organic solvents contemplated for Equation. E are tributyl-2-hydroxyethylphosphonium tetraphenylborate acetone, lower alkanol (ethanol, butanol), plus the Sol with melting point 124 C-125 C. Analysis of product vents listed hereinabove for Equation C. The reaction (Found: C, 80.03; H, 9.00; P, 5.35. CahsO requires: under Equation E, as shown in Example IV, supra, is C, 80.55; H, 9.25; P, 5.47%.). best carried out under inert conditions, such as under As is evident from this example, the halide salts of nitrogen. Other 2-haloethyl acetate reactants contem Equation A may be converted, in situ or after recovery plated herein are 2-bromoethyl acetate and 2-chloroethyl thereof, to the corresponding tetraphenylborate salts. acetate. Example II-Tributyl-2-acetoxyethylphosphonium Tables A, B, C, D and E, which follow, correspond bromide to Equations A, B, C, D and E, respectively. The exam ples in Tables A and B are carried out essentially as in -1,2-dimethoxyethane (275 milliliters), freshly distilled Examples I and II, respectively, supra, excepting of from calcium hydride, 2-bromoethanol (133 grams, 1.06 75 course as shown in Tables A and B. The examples in 5 3,409,707 6 Table C are carried out essentially as in Example LX, as in Example LX, infra. The examples in Table E infra, excepting of course as shown in Table C. Like are carried out essentially as in Example IV, supra, wise, the products of Table D are recovered essentially excepting of course as shown in Table E.

TABLE A G 69 R1R2R3P -- XCHCHOH - RR2R3PCHCHOH.X

R2 Moles X Moles Solvent Milliters Temp., Product Erple R RiR2R3P XCHCHOH of Solvent o C. 2-hydroxyethyltri V------CH, C3 Br 1.0 DME---- 1,500 70 methylphospho CHs nium bromide. 83 2-hydroxyethyltri VI.------n-C4H9 n-C.H. In-CH Cl 1,0 DME------1,500 butylphospho uium chloride. VII. n-C.H. n-CH 1. Cl 2 Dioxane--- 1,200 01. D0. 101 2-hydroxyethyltri VIII------n-C4H9 n-CH 1,2 ----do----- 2,000 butylphospho nium iodide. C 0,9 Ethyl 1,800 50 2-hydroxyethyltri IX------i-CH9 i-CH acetate. isobutylphos phonium chloride. 83 2-hydroxyethyltri X------n-C8H17 Cl 1.1 DME------1,700 octylphospho nium chloride. 83 2-hydroxyethyltri XI.------m-C12H25 1. Cl 1.1 1,700 dodecylphospho nium chloride. 30 2-hydroxyethyltri XII------C18H33 C. Has Cish33 Cl i.3 1,600 hexadecylphos phonium chloride. 200 2-hydroxyethyl XIII------C2H5 CHs Cl 1.0 Dioxane--- 1,700 triethyl phosphonium chloride. 2-hydroxyethyl XIV-...--- CHg Cas 1. Cl 1.1 2,000 45 butylethylhexyl phosphonium chloride.

2-hydroxyethyl XV------Cas 1 Cl 1.2 Dioxane--- 1,800 75 diethyl-2-ethoxy ethylphosphonium chloride. 60 2-hydroxyethyl XVI-...-- Br 1.3 DME - 1,600 tricyclohexyl phosphonium bromide.

2-hydroxyethyl Cl 0.9 DME------2,000 80 tricyclopentyl phosphonium chloride. 2-hydroxyethyl I 1. Dioxane-... 1,500 90 diphenylnaphthyl phosphonium iodide.

2-hydroxyethyltri I 1.0 - do------2,000 101 phenylphos phonium iodide.

Ethylace 65 2-hydroxyethyltri 1. Cl ... 2 1,600 (para-chloro tate. phenyl)phospho nium chloride.

2-hydroxyethyltri 1. Cl ... 3 DME------1,700 83 (para-tolyl)phos phonium chloride.

DME = dimethoxyethane. 2 THF = tetrahydrofuran. 3,409,707

- TABLE B. - "...... ; ...... e. f : . . . . G...... d.s.l....G. . . ." - R1R2R3PCH2CH2OH.X -- A -- R1R2R3PCHCEOY.X. Product Example of e Moles 6 A. Moles Solvent, Temp., Product No. Esple R3PCH2CH2OH.X. A. milliliters (ml.) o C. O. 1.0 Isopropenyl acetate. -- 3.2 OME, 300 ml.------83 2-acetoxyethyltrimethylphos 1,0 Dimethylsulfate------3.8 Dioxane, 300 ml.-- 90 2-methylsulfatoethyltributylphosphonium, bromide, ...... phonium chloride. - 0.8 . Acetic anhydride----- 1.0 Agee acid, 300 120 2-tolyethyltributylphosphonium ...... I...... ; COTCie. 0.9 Nitrosyl chloride------i.1 Digly me.------120 256thyltributylphosphonium. ; 0, ". ----- 3:1.2 :DME, 500 ml ----- 30 2-acetoxyethyltriisobutylphos.,10CC. - . , 1.0; p-Toluenesulfonyl*::::...... 1.0, .DME, . . . . 200 ml ----- 60 2-(p-toluenesulfonyloxy)ethyltriphonium chloride. 2.0 Trimethylchloride. phosphate-- 1. - Acetic acid,- 500 - - - 80 2-dimethylphosphatoethyltriethyldodecylphosphonium chloride. - ml. phosphonium chloride. - 1.0 Propionic acid.------. 2.4 DMF, 300 ml...-- 10 2-propionyloxyethyltrihexadecyl phosphonium chloride. ... O Butanoic anhydride--- . 1.0 DMF, 1,000 ml -- 30 2-butyryloxyethylbutylethylhexyl-, phosphonium chloride. 0.8 Acetic acid--- - 4.0 None ------18 2-acetoxyethyldiethyl-2-ethoxy ethylphosphonium chloride. 0.9 Acetyl chloride- - . . 0 DME, 200 ml ---...- ... 65 2-acetoxyethyltricyclohexylphos phonium bromide. 1.0 Hexanoyl chloride--...- : 1.9 Dioxane, 150 ml -- 1:25 2-hexanoyloxyethyltricyclopentyl-, phosphonium chloride. 1.0 Acetic anhydride- 6.0 100 2-acetoxyethyltriphenylphospho nium iodide. XXXV------XVIII.---- 1. Steary chloride-- 3.3 DME, 700 ml ---...- : 50 2-stearyloxyethyldiphenylnaphthyl phosphonium iodide. XXXVI.----- XX------1.0 Dodecanoyl bromide. 4.0 DMF, 1,000 ml.-- 40 2-dodecanoyloxyethyltriglor:phenyl)phosphonium (para XXXVII------XXI.------1.0 Phenylsulfonyl , 1.0 Dioxane, 600 ml.-- 65 2-(phenylsulfonyloxy)ethyltrichilloride...... bromide. (para-tolyl)phosphonium chloride. XXXVIII---- V------0 Ethylchloroformate--- 2.0 Diglynne, 300 ml.-- 40 2-(ethoxycarbonyloxy)ethyltri XXXIX.-----. VII------0.9 Dipropyl carbonate...- 3, 0 DME, 250 ml -----. 100 2-(propoxycarbonyloxy)ethyltrimethylphosphonium bromide. butylphosphonium chloride. X------VII------1.0 Ketene------1.0 THF, 500 ml.------75 2-acetoxyethyltributylphosphonium - . . . chloride. : - ...... 1 DMF = dinnethylformamide.

TABLE C 69 G 69 G RiR2R3PCHCHOY,X + Base - R. R2R3PCH=CH2X Example Product of Moles of Moles of Solvent, Temp., No. Example No. 69 G Base Base Milliliters (ml.) o C. Product R1R2R3PCHCHOY-X XLI.------XXII------1.0 K2CO3-...------... 1.0 DME, 300ml. 83 vinyltrimethylphosphonium XLII------XXIII------1. 0 Na2CO3------. 2.0 Dioxane, 300 ml. 00 vEylphosphoniumOlCle. XLIII-----. XXIV------1.0 LiCO3------4.0 Ely Aetate. 80 COCle.Do. v l XLIV.------XXV------2.0 - Mg(CO3).------8.0 Diglyme------100 Vybutylphosphonium - - s. lOdilde...... XLV--...-- - XXVI.------0.5 Ba(OH)2.------1.0 Astonitrile, 500 80 Vytisobutylphosphonium COce. XVI-...---- XXVII------0.9 Ca(OH)2------1. THF, 600m---- 60 Vytisodecylphosphonium XLVII.--- XXVIII------1.0 Polymeric trimethyl- 4.0 DME, 400 ml------85 Vinyltriethylphosphoniumchloride. . . - : . . benzyl ammoniuim - . chloride... ." chloride. - XLVIII---- XXIX------1.0 KOH------I.0 THF------50 Vinyltrihexadecylphosphoni um chloride. XLIX------XXX------0. HaON------0 Acetolitile----- 20 Vinylbutylethylhexylphos phonium chloride. L------XXXI.------1.0 LiOH------1:0 ----- do------GO Vinyldiethyl-2-ethoxyethyl rv phosphonium chloride. II------XXXII------i. 0 Mg(OH)2.------3.0 THF------2 Vinyltricyclohexylphosphoni um bromide. LII. -- XXXIII------2.0 Ca(CO3).-- 1.0 Dioxaile; 80 Vinyltricyclopentylphosphoni r um chloride. LIII------XXXIV------0.5 Ba(CO3).-- - - , 0 DME S. visitiphenylphosphonium LIV------XXXV------3.0 Polymeric triethyl- 1.0 Dioxane------. 97 . VinyldiphenylnapthylphosOddle. . hydroxide.benzyl ammonium plhonium iodide. LV------XXXVI------i, 0 ----- do------5.0 50 Vinyltri (para-chlorophenyl) phosphonium chloride. LV- XXXVII. O Activated alumina. 1.0 THF------35 Vinyltri(para-tolyl)phos phonium chloride. LVII.------XXXVIII---- .0 - Tetramethyl- 1.7 Digly me------42 Vinyltrimethylphosphoniu - ammoniunilhydroxide. bromide. 2.9 Tetrapropylanaimoni- 1.0 37 Vinyltributylphosphonium um hydroxide. chloride. Tetrabenzylammoni- i. O 25 Do. - - - - - um hydroxide, ------, , . 1 When not specified the amount of solvent employed is 500 milliliters. ‘. ... -- 3,409,707

TABLE D 69 G base GD 6 R1R2R3P CECEI2OH.X - RR2R3P CH-CH2-X - 100 C-250° C.

Example Product of Temp., Dehydrating 500Milliliters No. Example Base C. Agent of Solvent Product No. ------VI-...-- - -- Na2CO3------120 Silica gel ------DME------Vinyltributylphosphonium chloride. Ca(OH)2. - 100 Silica-alumina 2.---- DME - Vinyltridodecylphosphonium chloride. Li2CO3--- - 220 ------THF----- Vinyltrihexadecylphosphonium chloride. LiOH---- - 180 Silica-alumina 2----- Dioxane----. Vinyldiethyl-2-ethoxyethylphosphonium chloride. 150 Silica gel ------DME------Vinyltricyclohexylphosphonium bromide. - 250 ------Dioxane---- Winyldiphenylnaphthylphosphonium iodide. - 205 ------do------Vinyltriphenylphosphonium iodide. - 200 -- -- DME------Vinyltripara-chlorophenyl)phosphonium chloride. 9------XXI.------Activated alumina---- 175 ------DME------Vinyltri(para-tolyl)phosphonium chloride. Finely-divided particulates. 2 Finely-divided particulates.

TABLE E Example O Temp., No. : o C. Solwent Product

- R1R2R3P (----> XCH2CH2OC-CH3 ------; - -

10------Tridodecylphosphine------X= Bl Reflux. - Ethanol-...------Tillyl-2-acetoxyethylphosphoniumOnlice. 1l------Tricyclohexylphosphine------X=I 85------Acetonitrile------Tieghexyl-2-acetoxyethylphosphoniumiodide. 12------Tris(2-chlorophenyl)phosphine---- X = Cl Reflux.-- Acetone.------Tris(2-chlorophenyl)-2-acetoxyethylphosphonium chloride. 13. ------Tri(2-methoxypentyl)phosphine- X=I 50------Dioxane------2-acetoxyethylphosphonium iodide.

By finely-divided particulates in Table D is intended melting point 148 C-150° C.). Further recrystallization 28 to 200 mesh. Larger or smaller particulates are like- from ethylacetate-acetonitrile raises the melting point to wise within the purview of the instant discovery. 65 151.5°Pursuant C. to to152.5° the C.present discovery, the products of Example LX-Tributylvinylphosphonium bromide Tables B, C, D and E, hereinabove, may be converted Tributyl - 2 - acetoxyethylphosphonium bronide (23.7 to their corresponding sulfur-containing derivatives by re millimoles) is dissolved in 1,2-dimethoxyethane (25 milli- action with sulfhydryl (e.g., an alkyl mercaptan, an al liters) and sodium carbonate (5.0 grams, 47 millimoles) kane dithiol, a benzenethiol, a dialkylphosphorodithioate, is added. The mixture is stirred at reflux under nitrogen 70 an O,O-dialkylphosphorodithiolate, and the like) at a tem for 8 hours. The solid is filtered off and washed with hot perature in the range 20° C. to 200° C. Table F, G, H. 1,2-dimethoxyethane. The combined filtrates are evapo- which follows illustrates this reaction, the examples in rated to leave a semi-solid residue. Recrystallization from said table being carried out essentially as in Example ethyl acetate yields product tributylvinylphosphonium LXXVI, infra, excepting of course as specified in the bromide (3.3 grams, 10.7 millimoles, 45% yield with 75 table:

3,409,707 15 16 EXAMPLE LXXVI the group consisting of lower alkoxy, and cyano and said substituents for phenyl being selected from the group consisting of lower alkyl and , chlorine or ; t(CH), P-CH, CHis (OCH) (PBre A and A' each represent a member from the group con Potassium O,O-diethylphosphorodithiolate (13.0 grams, sisting of lower alkyl and lower alkoxy; X represents 0.06 mole) is dissolved in 50 milliliters of acetone and bromine, chlorine or iodine. i added dropwise to a stirred solution of tributylvinylphos phonium bromide (15.4 grams, 0.05 mole) in 50 milli 2. The compound of the formula liters of acetone. After standing overnight at room tem S perature, the mixture is filtered to remove precipitated (C4H9)3P CHCHSP (CH, PCIe potassium bromide and the acetone filtrate is treated with 0 3. A method which comprises bringing into reactive 10 milliliters of 10% hydrobromic acid. Upon treating contact the phosphonium salt of the formula the resulting mixture with diethyl ether the product phosphonium salt. S 5 and a sulfhydryl of the formula is obtained in nearly quantitative yield as a viscous syrup. AfPSH Obviously, from Tables F, G, H, the symbols R, R2, R3, Y and X have the meanings given hereinabove in cor A.' ... . . respond Equations A, B, C, D and E. The remaining sym 20 in the presence of an inert organic solvent and recovering bols in Equations F, G and H of Tables F, G, H have the corresponding salt of the formula: the following meanings: A R represents alkyl or alkylene having from 1 to 12 car bon atoms; benzyl; trialkylsilyl in which the alkyl moiety RRR PolichskA. f xe has from 1 to 8 carbon atoms; benzene; toluene; Xylene; R, R2, and R3 in the above formulae each represent a and 2-mapththylene. member selected from the group consisting of alkyl n is selected from 1 and 2. C1-C1s, substituted alkyl C1-C1s, cycloalkyl, phenyl, sub A and A' each represent lower alkyl and lower alkoxy. stituted phenyl, and naphthyl, said substituents for alkyl Q and Q’ each represent H, lower alkyl, or, when taken 30 being selected from the group consisting of lower alkoxy together, the residue of the phenyl radical. and cyano and said substituents for phenyl being selected Z represents S or O. from the group consisting of lower alkyl and bromine, As is evident from Tables F, G, H, above, the reac chlorine or iodine; X represents bromine, chlorine or tions contemplated therein using 2-acetoxyethylphos iodine; A and A' each represent a member from the group phonium salts as reactants are carried out in the pres consisting of lower alkyl and lower alkoxy. ence of a base of the type illustrated hereinabove for 4. A method which comprises bringing into reactive Equation C. By the same token, the vinylphosphonium contact a phosphonium salt of the formula salt reactants of Equations F, G and H, respectively, of Tables F, G, H may be reacted as shown in said table RiR-Rich, CH,0YR using or omitting a base. Furthermore, the solvents of 40 and a sulfhydryl of the formula Equation C, supra, are contemplated for the reactions of Equations F, G and H, as well as atmospheric, sub-at As mospheric and super-atmospheric conditions. Similarly, PSH an excess of either reactant with respect to the other is A? contemplated, although stoichiometric amounts are gen 45 in the presence of an inert organic solvent and a base erally employed. It will be noted from Tables F, G, H. (cf. particularly Example LXXI) that tertiary alkyl and recovering the corresponding salt of the formula (lower) amines are likewise contemplated as bases. The Rir2R3P CHCHSP5 AD Xe amount of base used in the examples of Tables F, G, H. 50 is 1 percent, based upon the total weight of reactants 1 YA p and 2. Generally, from about .01 percent to about 10 per cent may be used. R, R, and R8 in the above formulae each represent a The products of Equations F, G, H are useful as fire member selected from the group consisting of alkyl C retardants in plastics in the same manner described here C16, substituted alkyl C1-C1s, cycloalkyl, phenyl, sub inabove for the products Equations A, B, C and D. 55 stituted phenyl, and naphthyl, said substituents for alkyl Clearly, the instant discovery encompasses numerous being selected from the group consisting of lower alkoxy modifications within the skill of the art. Consequently, and cyano and said substituents for phenyl being selected while the present invention has been described in detail from the group consisting of lower alkyl and bromine, with respect to specific embodiments thereof, it is not chlorine or iodine; X-represents bromine, chlorine or intended that these details be construed as limitations upon 60 iodine; A and A' each represent a member from the group the scope of the invention, except insofar as they appear consisting of lower alkyl and lower alkoxy; Y represents in the appended claims. the acidic residue of an esterifying agent. What is claimed is: 1. The compound of the formula References Cited 65 UNITED STATES PATENTS S A Tee I/ 2,632,020 3/1953 Hoegberg ------260-978 X RRRPCHCIlse Xe 2,794,041 5/1957 Norman et al. 260-978 X A. 2,972,628 2/1961. McConnell et al., 260-982 X wherein R, R, and Reach represent a member selected from the group consisting of alkyl C1-C1s, substituted 70 CHARLES B. PARKER, Primary Examiner. alkyl C1-C16, cycloalkyl, phenyl, substituted phenyl, and A. SUTTO, Assistant Examiner. naphthyl, said substituents for alkyl being selected from