United States Patent (19) 11 Patent Number: 4,874,897 Bickelhaupt et al. (45. Date of Patent: Oct. 17, 1989

(54) BISPHOSPHINE PRODUCTION (56) References Cited U.S. PATENT DOCUMENTS 75 Inventors: Friedrich Bickelhaupt; Thomas van 3,036,132 5/1962 Belker ...... 568/17 der Does, both of Amsterdam, Netherlands 3,382,173 5/1968 Zorn et al...... 568/17 Primary Examiner-John Doll 73) Assignee: Shell Oil Company, Houston, Tex. Assistant Examiner-Short L. Hendrickson Attorney, Agent, or Firm-Dean F. Vance 21 Appl. No.: 190,187 57 ABSTRACT (22 Filed: May 4, 1988 Bisdicalkoxyphenyl)phosphinoalkanes are produced by reacting an alkoxyphenyl Grignard with phosphorus (30) Foreign Application Priority Data trichloride and converting the resulting dialkoxy phenyl)phosphorus chloride to the corresponding phos May 5, 1987 NL Netherlands ...... 87O1058 phine. The di(alkoxyphenyl) is reacted with a 51) Int. Cl...... C07F 9/02 dihaloalkane to produce the desired bisphosphine. 52 U.S.C...... 568/13; 568/8 58) Field of Search ...... 568/13, 17, 8 7 Claims, No Drawings 4,874,897 1. 2 larly it relates to a process for the production of 1,3-bis BISPHOSPHINE PRODUCTIONg di(2-alkoxyphenyl)phosphinopropane. FIELD OF THE INVENTION DESCRIPTION OF THE INVENTION This invention relates to the production of bis(di(al 5 The process of the invention comprises a multi-step koxyaryl)phosphinoalkanes, and aparticularly to the reaction for the production of 1,3-bis(di(2-alkoxy production of 1,3-bis(di(2-alkoxyphenyl)phosphino phenyl)phosphino) he first of which involves multiple reactions but reactions which are conducted propane. without the necessity for isolation of chemical interme BACKGROUND OF THE INVENTION 10 diates. An appropriately substituted 2-alkoxyphenyl In contrast with the production of substituted phos Grignard reactant and phosphorus trihalide are con phines wherein the substituents are aliphatic, the pro tacted to produce a di(alkoxyphenyl)phosphorus halide duction of having aromatic substituents is which is converted to the di(alkoxyphenyl)phosphine frequently very difficult, depending on the particular by reaction with an -containing phosphine desired. Particular difficulties often arise 15 followed by hydrolysis. This phosphine is typically when mixed aryl-alkyl phosphines are desired. recovered and subsequently reacted with a 1,3-dihaloal The class of mixed aryl-alkyl phosphines is illustrated kane to produce the bisphosphine. by the bis(diphenylphosphino). Such bisphos The Grignard reactant employed in the process of the phines have demonstrated and widespread utility as invention is a 2-alkoxyphenylmagnesium halide wherein components of catalyst compositions which also in 20 the alkoxy is lower alkoxy of up to 4 carbon atoms clude Group VIII metal compounds. One use of such inclusive, preferably methyl, and the halide moiety is catalyst compositions is in the production of linear alter chloride or bromide, preferably bromide. Such Grign nating polymers of carbon monoxide and at least one ard reactants are produced by conventional techniques ethylenically unsaturated . These polymers 25 from the corresponding 2-alkoxyphenyl halide and have the repeating formula -CO-CA) A wherein A magnesium, typically in the presence of an ether or represents ethylenically unsaturated hydrocarbon poly other polar in which the Grignard reactant is merized through the ethylenic unsaturation. By way of soluble. For example, 2-methoxyphenyl bromide reacts further illustration, when the at least one ethylenically with magnesium in tetrahydrofuran to produce 2 unsaturated hydrocarbon is , the linear alternat methoxyphenylmagnesium bromide. Reaction condi ing pplymer is represented by the repeating formula 30 tions and reactant ratios for this conversion are well -CO-(CH2-CH2). Illustrative methods for the produc known but typically involve ratios of moles of 2-alkoxy tion of such polymers are disclosed in Published Euro phenylhalide togram-atoms of magnesium that are sub pean Patent Applications 121,965 and 181,014. The stantially 1:1 and a liquid phase reaction environment at catalyst compositions therein described include compo 35 a temperature that is dependent in part on the solvent sitions formed from a compound of a Group VIII metal employed but typically is no higher than about 50 C. such as a palladium carboxylate, the anion of a strong and frequently is much lower, e.g., a temperature as low non-hydrohalogenic acid and a bis(phenylphosphino)al as about -70' C. The reaction is conducted in an inert kane. The bis(diphenylphosphino)alkanes were particu atmosphere, customarily a nitrogen atmosphere. larly useful, especially bis(diphenylphosphino)propane. The Grignard reactant is employed without purifica For other modifications of the polymerization process, tion or isolation in the reaction with phosphorus trihal bis(substituted-phenylphosphino)alkanes have been ide which follows in the reaction sequence. This reac found to be useful, particularly 1,3-bisdic2-alkoxy tion is most easily accomplished by adding to the phos phenyl)phosphino-propane. Such a process is de phorus trihalide, preferably phosphorus trichloride, the scribed and claimed in copending U.S. patent applica 45 solution of Grignard reactant, also at a temperature of tion Serial No. 930,468; filed Nov. 14, 1986 from about -70' C. to about 50 C., and under an inert One method of producing bis(phenylphosphino)al reaction atmosphere such as nitrogen. The molar ratio kanes is shown by U.K. Patent Application 2,101,601. of the Grignard reactant to the phosphorus trichloride This process involves a multi-step process employing a which is usefully employed is from about 3:2 to about phosphonium salt as an intermediatre. An alternate 50 5:2 but preferably is substantially stoichiometric, e.g., process for the production is shown by Chatt et al., J. about 2:1. Chem. Soc. Dalton Trans, pp. 1131-1136 (1985). The The resulting product is a di(2-alkoxyphenyl)phos Chatt et al process involves the use of a bis(dichloro phorus halide, for example, di(2-methoxyphenyl)phos phosphino), the production of which is said to phorus chloride, which is isolated by conventional tech require iron equipment which slowly degrades during 55 niques such as precipitation, extraction or distillation reaction. A method described in copending U.S. patent but which is preferably employed in situ in the succeed application Serial No.07/175,021, filed Mar. 30, 1988 ing reaction. This in situ reaction without purification is (Attorney's Docket No. T-0283) comprises reaction permitted by the selectivity to the di(alkoxyphenyl)- of a dihaloalkane and an alkali metal (di(alkoxyphenyl)- phosphorus halide which selectivity is quite high with phosphide produced by reaction of elemental alkali 60 little or no production of (2-alkoxyphenyl)phosphorus metal and the corresponding tri(alkoxyphenyl)phos dihalide or tri(2-alkoxyphenyl)phosphine. phine. It would be of advantage to provide an alternate The di(2-alkoxyphenyl)phosphorus halide is con method for producing bis(alkoxyphenyl)phosphino al verted to the corresponding di(2-alkoxyphenyl)phos kanes. phine by reaction with a metal hydride followed by 65 hydrolysis. The reaction with metal hydride is most SUMMARY OF THE INVENTION easily conducted by adding the metal hydride to the This invention relates to a process for the production solution in which the di(2-alkoxyphenyl)phosphorus of bis(alkoxyphenyl)phosphine alkanes. More particu halide is formed. The metal hydride is added to the 4,874,897 3 4. solution and the mixture is maintained at reaction tem ethylenically unsaturated hydrocarbon, illustratively perature until reaction has taken place. produced by the process of the above copending U.S. The metal hydride employed as a reactant is a hy patent application Ser. No. 930,468, filed Nov. 14, 1986. dride of a strong metal but is preferably an alkali metal The catalyst composition of this application comprises, containing hydride including alkali metal such inter alia, a palladium carboxylate such as palladium as , hydride and potassium hy acetate, the anion of a strong non-hydrohalogenic acid dride as well as mixed metal hydrides containing alkali such as trifluoroacetic acid or p-toluenesulfonic acid, metal moieties such as lithium aluminum hydride and and a bidentate phosphorus ligand. sodium borohydride. The preferred alkali metal-con The invention is further illustrated by the following taining hydride is lithium aluminum hydride. This reac 10 Illustrative Embodiments which should not be con tion takes place over a wide range of reaction tempera strued as limiting. tures and suitable reaction temperatures are from about -70' C. to about 70° C. A convenient reaction temper ILLUSTRATIVE EMBODIMENT I ature is the reflux temperature of the reaction mixture. A Grignard reagent solution (2-methoxyphenylmag Suitable reaction pressures are those sufficient to main 15 nesium bromide) was produced from 61.0g of 2-methox tain a non-gaseous phase reaction mixture. Subsequent yphenyl bromide and 9.5g magnesium in 350 ml of tetra to reaction of the di(2-alkoxyphenyl)-phosphorus halide hydrofuran. This solution was filtered through glass and the alkali metal-containing hydride, the product wool, cooled to -60 C. and, under nitrogen, dripped mixture is hydrolyzed, preferably by contact with an into a solution of 21.8g phosphorus trichloride in 400 ml excess of an aqueous solution of a strong electrolyte salt 20 tetrahydrofuran. After standing overnight at ambient such as an ammonium salt. A saturated solution of am temperature, the solution was cooled again to -60 C. monium chloride in water is a particularly effective and 2.2g of lithium aluminum hydride was added. The hydrolysis media. resulting solution was stirred for one hour at -60C., The resulting product is a di(2-alkoxyphenyl)phos warmed to room temperature and then heated to 50 C. phine which is isolated by conventional methods as 25 and maintained at that temperature for three hours. The described above. The secondary phosphine is produced solution was then cooled to 0 C. and saturated ammo in good yield, but the effective yield is even higher since nium chloride was added. The tetrahydrofuran layer the major by-product is the corresponding di(2-alkoxy was separated and concentrated by evaporation. Distil phenyl)phosphine oxide which is able to be reduced by lation of the product mixture thus obtained afforded well known methods to improve the yield of the sec 30 15.1g of di(2-methoxyphenyl)-phosphine, a 39% yield, ondary phosphine or alternatively the phosphine oxide b.pt 130 C. at 0.05 mm. The 15 g residue was princi is recycled to an earlier reaction step to thereby pro pally the corresponding di(2-methoxyphenyl)phosphine mote the production of additional secondary phosphine. oxide, from which additional di(2-methoxyphenyl)- The final conversion of the process of the invention, phosphine could be obtained by reduction. and the second process operation, is reaction of the 35 A solution of dimsyl sodium in dimethyl sulfoxide di(2-alkoxyphenyl)phosphine and a 1,3-dihalopropane. was produced from 0.65g sodium hydride and 15ml Although chloro or bromo or mixtures are suitable halo dimethyl sulfoxide. This solution was then added to substituents on the 1,3-halopropane reactant, the pre 5.7g of di(2-methoxyphenyl)phosphine in 50ml of di ferred 1,3-dihalopropane reactant is 1,3-dichloropro methyl sulfoxide. The resulting mixture was heated to pane. The secondary phosphine and the 1,3-dihalopro 50° C. and 1.3g of 1,3-dichloropropane in 5 ml of di pane are contacted in the presence of a strong base in a methyl sulfoxide was added. The resulting mixture was polar organic solvent. Suitable strong bases include the heated to 50 C., maintained at that temperature for 3 alkali metal hydroxides such as sodium hydroxide and hours and then cooled to room temperature. When 50 potassium hydroxide. Also suitable, and generally pre ml of water was added to the reaction mixture, a white ferred, is the strong base of unknown structure termed 45 precipitate was obtained. The precipitate was recovered "dimsyl sodium' which is produced by reaction of so by filtration, washed with water and recrystallized from dium hydride and dimethylsulfoxide. Largely because . The product, 1,3-bis(di(2-methoxyphenyl)- of this presence of strong base, the preferred reaction phosphinopropane, 3.6g, 58% yield, was obtained in solvent for reaction of the secondary phosphine and the the form of white needles, m.pt. 149-150 C. 1,3-dihalopropane is also dimethyl sulfoxide although 50 other polar including ethers and sulfones are LLUSTRATIVE EMBODIMENT II suitable. When the procedure of Illustrative Embodiment I is The di(2-alkoxyphenyl)phosphine and the 1,3-dihalo repeated in substantially the same manner, except that propane are contacted in a molar ratio of from about 1:1 the first reaction sequence was conducted at room tem to about 4:1 but preferably in a ratio of from about 1.5:1 55 perature and the lithium aluminum hydride solution was to about 2.5:1. Reaction suitably takes place at a temper added to the di(2-methoxyphenyl)phosphine chloride ature from about 0° C. to about 70° C., preferably from solution, a good overall yield of the 1,3-bis(di(2-methox about 10 C. to about 30° C., and at a pressure sufficient yphenyl)phosphinopropane will be obtained. to maintain a non-gaseous reaction mixture. Subsequent What is claimed is: to reaction, the 1,3-bis(di(2-alkoxyphenyl)-phosphino 1. A process for the production of 1,3-bis(di(2-alkoxy propane is recovered by conventional methods such as phenyl)phosphinopropane which comprises (1) react described above. ing 2-alkoxyphenyl halide with magnesium, thereby The bis(alkoxyphenyl)phosphino propane is useful as producing the corresponding 2-alkoxyphenyl-mag a ligand of transition metal catalyst compositions which nesium halide; (2) reacting said 2-alkoxyphenylmag are employed to catalyze a number of chemical trans 65 nesium halide with phosphorus trihalide, thereby pro formations. One of the many examples of the use of such ducing the corresponding di(2-alkoxyphenyl)phos catalyst compositions is in the production of linear alter phorus halide; (3) producing from said di(2-alkoxy nating polymers of carbon monoxide and at least one phenyl)phosphorus halide the corresponding di(2- 4,874,897 5 6 alkoxyphenyl)phosphine by reaction with alkali metal 4. The process of claim 3 wherein the alkali metal containing hydride is lithium aluminum hydride. containing hydride followed by hydrolysis; and (4) 5. The process of claim 4 wherein the 1,3-dihalopro reacting the di(2-alkoxyphenyl)phosphine with 1,3- pane is 1,3-dichloropropane. dihalopropane in the presence of strong base, and re 5 6. The process of claim 1 wherein said hydrolysis in covering 1,3-bis(di(2-alkoxyphenyl)phosphinopropane step (3) comprises contacting said di(2-alkoxyphenyl)- from the resulting mixture. phosphine with a saturated solution of ammonium chlo ride in water. 2. The process of claim 1 wherein the 2-alkoxyphenyl 7. The process of claim 1 wherein said 1,3-bis(di(2- halide is a 2-methoxyphenyl halide. 10 alkoxyphenyl)-phosphinopropane is recovered in step 3. The process of claim 2 wherein the 2-methoxyphe (4) by filtration. nyl halide is 2-methoxyphenyl bromide. k k is 38

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