United States Patent (19) [11] 3,856,764 Throckmorton et al. (45) Dec. 24, 1974

54 POLYMERIZATION PROCESS 3,542,751 5f 1970 Throckmorton...... 260/94.3 75) Inventors: Morford C. Throckmorton; William 3,790,551 2/1974 Yagi et al...... 260/94.3 W. Saltman, both of Akron, Ohio Primary Examiner-William F. Hamrock 73) Assignee: The Goodyear Tire & Rubber Attorney, Agent, or Firm-F. W. Brunner, J. Y. Company, Akron, Ohio Clowney, R. A. Thompson 22 Filed: July 18, 1973 21 Appl. No.: 380,176 57) ABSTRACT Related U.S. Application Data A process for producing cis-1.4 polybutadiene by con tacting butadiene with a catalyst consisting of (1) at 63 Continuation-in-part of Ser. No. 202,024, Nov. 24, least one organoaluminum compound, (2) at least one 1971, abandoned. nickel compound selected from the class consisting of nickel salts of carboxylic acids, organic complex com (52) U.S. Cl...... 260/82.1, 260/94.3 punds of nickel, nickel tetracarbonyl, and (3) at least 51 Int. Cl...... C08d 1/14 one hydrogen fluoride complex prepared by complex 58 Field of Search...... 260/94.3, 82.1 ing hydrogen fluoride with a member of the class con 56) References Cited sisting of ketones, esters, ethers, alcohols, nitriles and UNITED STATES PATENTS Water. 3,513,149 5/1970 Smith et al...... 260/94.3 8 Claims, No Drawings 3,856,764 1. 2 POLYMERIZATION PROCESS compounds. Also included are diethylaluminum ethox This application is a continuation-in-part of applica ide, diisobutylaluminum ethoxode and di tion Ser. No. 202,024, filed Nov. 24, 1971 now aban propylaluminum methoxide. doned. The component of the catalyst of this invention This invention is directed to a method of polymeriza which contains nickel may be any organonickel com tion of butadiene and/or butadiene in mixture with pound. It is preferred to employ a soluble compound of other diolefins to form polymers with a high, i.e., 90 nickel. These soluble nickel compounds are normally percent or more, content of cis-1,4 addition. It is also compounds of nickel with a mono- or bi-dentate or directed to catalyst systems useful for this purpose. ganic ligand containing up to 20 carbon atoms. "Li Such polymers have been found to possess properties 10 gand' is defined as an ion or molecule bound to and which make them useful as synthetic rubbers. considered bonded to a metal atom or ion. Monoden It is an object of this invention to provide a method tate means having one position through which covalent whereby butadiene can be polymerized to a high, i.e., or coordinate bonds with the metal may be formed; bi 90 to 98 percent, content of cis-1,4-polybutadiene. An dentate means having two positions through which co other object is to provide a catalyst system by which 15 valent or coordinate bonds with the metal may be these polymerizations may be accomplished. Another formed. By the term "soluble' is meant soluble in inert object is to form copolymers of isoprene and butadiene solvents. Thus, any salt or an organic acid containing in which the polybutadiene segment has a high content from about 1 to 20 carbon atoms may be employed. of cis-1,4 structure. Other objects will become appar Representative of organonickel compounds are nickel ent as the description proceeds. 20 benzoate, nickel acetate, nickel naphthenate, nickel According to the invention, butadiene or butadiene octanoate, bis(a-furyl dioxime) nickel, nickel palmi in mixture with other diolefins is polymerized, by con tate, nickel stearate, nickel acetylacetonate, nickel sali tacting under solution polymerization conditions, with caldehyde, bis(salicylaldehyde) ethylene diimine a catalyst consisting essentially of (1) at least one or nickel, bis(cyclopentadiene) nickel, cyclopentadienyl ganoaluminum compound, (2) at least one nickel com 25 nickel nitrosyl and nickel tetracarbonyl. The preferred pound selected from the class consisting of nickel salts component containing nickel is a nickel salt of a car of carboxylic acids, organic complex compounds of boxylic acid or an organic complex compound of nickel, nickel tetracarbonyl and (3) at least one hydro nickel. gen fluoride complex prepared by complexing hydro The component of the catalyst of this invention gen fluoride with a member of the class consisting of 30 which contains the hydrogen fluoride associated com ketones, ethers, esters, alcohols, nitriles and water. plexes should be compounds which readily associate By the term "organoaluminum compound' is meant themselves with hydrogen fluoride. any organoaluminum compound responding to the for The compounds which associate with the hydrogen mula: - fluoride to form this component of the catalyst, are the 35 type that are capable of associating with the hydrogen fluoride because of its strong hydrogen bonding char Y, acter. Such compounds of association contain an atom or radical which is capable of lending electrons to or in which R is selected from the group consisting of sharing electrons with hydrogen fluoride. Compounds alkyl (including cycloalkyl), aryl, alkaryl, arylalkyl, 40 capable of associating are ethers, alcohols, ketones, es alkoxy, hydrogen and fluorine, R and Rs being se ters, nitriles and water. lected from the group of alkyl (including cycloalkyl), aryl, alkaryl, and arylalkyl. Representative of the com The ketone subclass can be defined by the formula pounds responding to the formula set forth above are: O diethyl aluminum fluoride, di-n-propyl aluminum fluo 45 R&R ride, di-n-butyl aluminum fluoride, diisobutyl alumi num fluoride, dihexyl aluminum fluoride, dioctyl alu where R' and R represent alkyl, cycloalkyl, aryl, alkaryl minum fluoride, and diphenyl aluminum fluoride. Also and arylalkyl radicals containing from 1 to about 30 included are diethyl aluminum hydride, di-n-propyl carbon atoms; R' and R may be the same or dissimilar. aluminum hydride, di-n-butyl aluminum hydride, diiso 50 These ketones represent a class of compounds which butyl aluminum hydride, diphenyl aluminum hydride, have a carbon atom attached by a double bond to oxy di-p-tolyl aluminum hydride, dibenzyl aluminum hy gen. Representative but not exhaustive of the ketones dride, phenyl ethyl aluminum hydride, phenyl-n-propyl useful in the preparation of the ketone-hydrogen fluo aluminum hydride, p-totyl ethyl aluminum hydride, p ride complexes of this invention are dimethyl ketone, tolyl n-propyl aluminum hydride, p-tolyl isopropyl alu 55 methyl ethyl ketone, dibutyl ketone, methyl isobutyl minum hydride, benzyl ethyl aluminum hydride, benzyl ketone, ethyloctyl ketone, 2,4-pentanedione, butyl cy n-propyl aluminum hydride, and benzyl isopropyl alu cloheptanone, acetophenone, amylphenyl ketone, minum hydride and other organoaluminum hydrides. . butylphenyl ketone, benzophenone, phenyltolyl ke Also included are trimethyl aluminum, triethyl alumi tone, quinone and the like. The preferred ketones to num, tri-n-propyl aluminum, triisopropyl aluminum, 60 form the ketone-hydrogen fluoride of this invention are tri-n-butyl aluminum, triisobutyl aluminum, tripentyl the dialkyl ketones of which acetone is most preferred. aluminum, trihexyl aluminum, tricyclohexyl aluminum, The nitrile subclass can be represented by the for trioctyl aluminum, triphenyl aluminum, tri-p-tolyl alu mula RCN where R represents an alkyl, cycloalkyl, minum, tribenzyl aluminum, ethyl diphenyl aluminum, 65 aryl, alkaryl and arylalkyl and contain up to about 30 ethyl di-p-tolyl aluminum, ethyl dibenzyl aluminum, di carbon atoms. The nitriles contain a carbon atom at ethyl phenyl aluminum, diethyl p-tolyl aluminum, di tached to a nitrogen atom by a triple bond. Representa ethyl benzyl aluminum and other triorganoaluminum tive but not exhaustive of the nitrile subclass are aceto 3,856,764 3 4 nitrile, butyronitrile, acrylonitrile, benzonitrile, toluni which can be employed may be an alkyl, alkaryl, arylal trile, phenylacetonitrile, and the like. The preferred hy kyl or an aryl hydrocarbon. Benzene, for example, is a drogen fluoride-nitrile complex prepared from the ni convenient solvent system. triles is hydrogen fluoride benzonitrile complex. The complexes of this invention are usually prepared The alcohol subclass can be defined by the formula 5 by simply dissolving appropriate amounts of the com ROH where R represents alkyl, cycloalkyl, aryl, alka plexing agent for instance, a ketone, an ether, an ester, ryl, and arylalkyl radicals containing from about 1 to an alcohol, a nitrile or water, in a suitable solvent and about 30 carbon atoms. an appropriate amount of the hydrogen fluoride in a These alcohols represent a class of compounds which suitable solvent and mixing the two solvent systems. have a carbon atom attached by a single bond to oxy O The mixing of the complexing agents, except water, gen which is in turn attached to a hydrogen by a single should be done in the absence of water vapor. Another bond. Representative but not exhaustive of the alcohols possible method would be to dissolve either the hydro useful in the preparation of the hydrogen fluoride com gen fluoride or the complexing agent in a suitable sol plexes are methanol, ethanol, n-propanol, i-propanol, vent and adding the other component. Still another phenol, cyclohexanol, butanol, hexanol and pentanol. 15 method of mixing would be to dissolve the complexing The preferred hydrogen fluoride-alcohol complex is agent in a solvent and simply bubble gaseous hydrogen hydrogen fluoride phenolate complex. fluoride through the system until the complexing agent The ether subclass can be defined by the formula is reacted with hydrogen fluoride. The concentrations R'OR where R and R' represent alkyl, cycloalkyl, aryl, may be determined by weight gain or chemical titra alkaryl, and arylalkyl radicals containing from about 1 20 tion. The amount of complexing agent cannot be spe to about 30 carbon atoms; R and R' may be the same cifically set down. The amount of complexing agent or dissimilar. The R's may also be joined through a may be a range depending on the conditions of the re common carbon bond to form a cyclic ether with the action system, the hydrogen bonding strength of the ether oxygen being an integral part of the cyclic struc complexing agent the size of the complexing agent, or ture such as tetrahydrofuran, furan or dioxane. These 25 it may be an equilibrium between the hydrogen fluoride ethers represent a class of compounds which have two complex and the hydrogen fluoride plus the complex carbon atoms attached by single bonds to an oxygen ing agent. atom. Representative but not exhaustive of the ethers The three catalyst components of this invention can useful in the preparation of the hydrogen fluoride com be charged separately to the reactor containing the bu plexes of this invention are dimethyl, diethyl, dibutyl, 30 tadiene and/or mixtures thereof with other diolefins diamyl, diisopropyl ethers, or tetrahydrofuran, anisole, and the solvent system therefor, either stepwise or si diphenyl ether, ethyl methyl ether, dibenzyl ether and multaneously. It has been discovered that when the the like. The preferred hydrogen fluoride-ether com three catalyst components of this invention are mixed plexes formed from the ethers are hydrogen fluoride together outside of the reactor and then added to the diethyl etherate and hydrogen fluoride dibutyl etherate 35 reactor, the catalyst system is not very active. Thus, the complexes. catalyst should not be preformed by mixing the three The ester subclass can be defined by the formula: catalyst components together prior to contacting buta diene. O However, an improved preformed catalyst system R-6-0-R 40 can be prepared by mixing the three catalyst compo nents together while in the presence of a small amount wherein R and R' are represented by alkyl, cycloalkyl, of a conjugated diolefin, for example, butadiene or iso aryl, alkaryland arylalkyl radicals containing from 1 to prene. It appears that by mixing the three catalyst com about 20 carbon atoms. The esters contain a carbon ponents together in the presence of the small amount atom attached by a double bond to an oxygen atom as 45 of a diolefin seems to stabilize the catalyst system and indicated. Representative but not exhaustive of the es allows the formation of a very active preformed cata ters are ethylbenzoate, amyl benzoate, phenyl acetate, lyst. phenyl benzoate and other esters conforming to the The diolefin apparently reacts with the catalyst com formula above. The preferred hydrogen fluoride-ester ponents to form a catalyst complex which is more sta complex is hydrogen fluoride ethyl benzoate complex. 50 ble and active, particularly when the polymerization Hydrogen fluoride is a limpid liquid which fumes system contains more impurities than the "in situ' cat strongly in air, is very poisonous, forms ulcerated sores alyst where the individual catalyst components are if it comes in contact with the skin, and is very danger added to the reactor containing a very large amount of ous to handle or manipulate. By complexing the hydro monomer and then allowed to react with each other. gen floride with the complexing agents heretofore men 55 The improved preformed catalyst may be prepared by tioned, some of the advantages of this invention are a dissolving a small amount of diolefin in a hydrocarbon safer, easier and more accurate way of handling the hy solvent such as benzene or hexane and then adding the drogen fluoride component of the catalyst system. Hy organoaluminum component, the Ni component and drogen fluoride complexes usually have a lower vapor then the HF-complex component to the solvent. pressure and do not fume as badly as does hydrogen 60 The particular order of addition in preforming the fluoride. Hydrogen fluoride boils at 19.7°C. whereas a catalysts may be varied somewhat, but it is advanta 40 percent by weight of hydrogen fluoride diethyl ether geous to have (1) the diolefin present before the addi azeotrope boils at 74°C. When the hydrogen fluoride is tion of both the organoaluminum and Ni components complexed, the corrosiveness of the hydrogen fluoride and (2) the Nicomponent present before the addition is reduced. The hydrogen fluoride complex can be dis 65 of both the organoaluminum and HF-complex catalyst solved in a solvent and, thus, can be handled and components. The amount of the diolefin which can be charged to the system as a liquid solution. The solvent present to form the improved preformed catalyst can 3,856,764 S 6 be varied over a wide range, and of course, is somewhat The temperatures employed in the polymerizations dependent on the other catalyst concentrations. of this invention are not critical and may vary from a The amount of diolefin used to preform the catalyst very low temperature such as -10°C. or below up to may be within the range of about 0.001 to 3 percent of high temperatures such as 100°C. or higher. However, the total amount of monomer to be polymerized. Ex it is usually more desirable to employ a more conve pressed as a mole ratio of conjugated diolefin to nickel nient temperature between about 30° and about 90°C. complex, the amount of diolefin present during the pre The practice of this invention is further illustrated by forming step can be within the range of about 1 to reference to the following examples which are intended about 3,000 times the concentration of nickel. The pre to be representative rather than restrictive of the scope ferred mole ratio of conjugated diolefin to nickel is 10 of this invention. Unless otherwise noted, all parts and about 5:1 to 500:l. It is most preferred to use about percentages are by weight. Dilute solution viscosities 50:1 to about 100: 1. (DSV) have been determined in toluene at 30°C. This three-component catalyst system has polymer ization activity over a wide range of catalyst concentra EXAMPLE I tion and catalyst ratios. The three catalyst components 15 A purified butadiene in benzene solution containing interreact to form the active catalyst. As a result, the 10 grams of butadiene per hundred milliliters of solu optimum concentration for any one catalyst is very de tion was charged to a number of 4-ounce bottles. Nitro pendent upon the concentrations of each of the other gen blanketed the premix while the catalysts were two catalyst components. Furthermore, while polymer charged "in situ'. The catalysts added were (a) trieth ization will occur over a wide range of catalyst concen 20 ylaluminum (TEAL) added as a 0.25 molar (M) solu trations and ratios, polymers having the most desirable tion in benzene, (b) 0.05 M nickel octanoate (NiOct) properties are obtained over a narrower range. Poly in benzene, and (c) 0.50 M hydrogen fluoride die merization can occur while the mole ratio of the or thylether complex HF.ETO) in benzene. The bottles ganoaluminum compound (Me) to the organonickel were capped tightly, placed in a water bath maintained compound (Ni) ranges from about 0.371 to about 25 at 50°C. and then tumbled end-over-end for the periods 300/1; the mole ratio of hydrogen fluoride complex of time shown in Table 1. The polymerizations were (HFC) to the organonickel compound (Ni) ranges terminated by mixing the polymer cements with one from about 2/1 to about 300/1 and the mole ratio of hy part of both triisopropanolamine and dibutyl drogen fluoride complex to the organoaluminum com paracresol per hundred parts of original monomer pound ranges from about 0.2/1 to about 15/1. How 30 used. The resulting polybutadiene polymers were dried ever, the preferred mole ratios of Me/Ni ranges from under vacuum. about 2/1 to about 80/1, the preferred mole ratio of The amount of TEAL and of NiOct charged to each HFC/Ni ranges from about 5/1 to about 100/1 and the bottle was 0.1 and 0.0075 millimole; the amount of preferred mole ratio of HFC/Me ranges from about 35 HF.ETO was varied as shown in Table 1. Polymer 004/1 to about 711. yields and dilute solution viscosities (DSV) obtained on The concentration of the catalyst employed depends the polybutadienes also are presented in Table 1: on factors such as purity, rate desired, temperature and Table 1 other factors, therefore, specific concentrations cannot be set forth except to say that catalytic amounts are 40 Millimole per used. Some specific concentrations and ratios which Exp. 10 gm. BD," Pzn. Time, Yield, DSV produce elastomers having desirable properties will be No. HF.EtO Hours Wt. % diligm illustrated in the examples given herein to explain the t 0.08 8 2 ND3 2 0.13 31 ND teachings of this invention. 3 0.6 56 5.4 In general, the polymerizations of this invention are 45 4 0.25 1 8 4.6 carried out in an inert solvent, and are, thus, solution 5 0.30 1 62 3.0 6 0.30 i8 96 ND polymerizations. By the term “inert solvent' is meant 7 0.40 18 83 2.0 that the solvent or diluent does not enter into the struc 8 0.60 18 20 ND ture of the resulting polymer nor does it have any ad 9 1.00 8 6 ND verse effect on the activity of the catalyst employed. 50 B) = butadiene. Such solvents are usually aliphatic, aromatic, or cyclo Pzn. = polymerization. aliphatic hydrocarbons, examples of which are pen ND = not determined. tane, hexane, toluene, benzene, cyclohexane and the like. Preferred solvents are hexane and benzene. The EXAMPLE II solvent/monomer volume ratio may be varied over a 55 The procedure is the same as that in Example l ex wide range. Up to 20 or more to 1 volume ratio of sol cept that triisobutylaluminum (TIBAL) was used vent to monomer can be employed. It is usually pre rather than TEAL. ferred or more convenient to use a solvent/monomer volume ratio of about 3/1 to about 6/1. Suspension po Table 2 lymerization may be carried out by using a solvent, e.g., 60 butane or pentane, in which the polymer formed is in Millimole per soluble. It should be understood, however, that it is not Exp 10 gm. BD P2n. Time: Yield, DSW intended to exclude bulk polymerizations from the No. HF.EtO Hours Wit. A dign 0.08 19 O ND scope of this application. 65 2 0.13 19 80 5.5 It is usually desirable to conduct the polymerizations 3 0.16 80 4.8 4. 0.25 88 5.0 of this invention employing air-free and moisture-free 5 0.35 62 2.8 techniques. 6 0.45 19 86 2.0 3,856,764 7 8 Table 2-Continued EXAMPLE VI Millimole per The procedure is the same as that used in Example Exp. 10 gm. BD Pzn. Time Yield, DSV I; however, triisobutylaluminum (TIBAL), 0.10 milli No. HF.EtO Hours Wt. 9% di?gm 5 mole, is used instead of triethylaluminum (TEAL) and 7 0.60 9 43 1.4 various hydrogen fluoride alcoholates and water are 8 .00 19 7 ND used.

EXAMPLE III 10 Table 6 The procedure used is the same as Example I except Millimole per that the polymerization solvent was heptane instead of Exp. 10 gm. BD Pzn. Time, Yield, DSV benzene and the source of Ni is varied as shown in No. HFAlcoholate Hours Wt. digm Table 3. 15 0.4 Methanol 19.0 10.8 2 0.8 Methanol 19.0 4.4 - Table 3 3 0.4 Ethanol 90 8 - 4 0.8 Ethanol 9.0 5.3 -- 5 0.4 Propanol 190 49.4 8,31 Millimole per 6 0.8 Propanol 90 4.7 m Exp. Ni 10 gm. BD PZn. Time Yield, 7 0.4 Isopropanol 2.5 25.6 6.56 No. Compound HF.EtO Hours Wt. 9% 8 0.8 Isopropanol 19.0 9.5 - 20 9 0.4 Cyclohexanol 2.5 32.9 6.87 NiNaph 0.25 0.75 67 10 0.8 Cyclohexanol 9.0 15.4 04 Phenol 2.5 68.4 5.23 2 NiOct? 0.25 0.75 65 12 0.8 Phenol 19.0 704 2.66 3 NiAcAc 0.25 00 65 13 0.4 Water 9.0 700 4 Ni(CO) 0.25 00 70 5 NiAcAc 0.15 1.00 68 6 Ni(CO) 0.15 2.00 33 25 Nickel Naphthenate Nickel Octanoate * Nickel Acetylacetonate EXAMPLE VII Nickel Tetracarbonyl The procedure used is similar to that in Example I ex 30 cept that the catalyst is preformed in the presence of a EXAMPLE IV small amount of the monomer, butadiene. If the orga nometallic compound, Ni compound and HF complex The procedure used is the same as that used in Exam are mixed together before charging to the premix, the ple I except that different complexes of HF are com resulting gray slurry has almost no polymerizing cata pared as shown in Table 4. 35 lytic activity. However, if even a small amount of buta Table 4 diene or other conjugated diolefin is present, the pre formed catalyst is quite active. Butadiene must be pres Millimole per ent before the organometallic has an opportunity to Exp. 10 gm. BD PZn. Time Yield DSV react either with the Nicompound or the HF. No. HF.Complex Hours Wt. dl/gm 40 In this example the standard order of addition for 0.25 HF.EtO 80 4.7 mixing the catalyst components was: 2 0.30 HF.EtO 2 77 4.0 1. Solvent 3 0.25 HF.BuO l 60 4.7 4 0.30 HF.BuO 55 4.3 2. Butadiene 5 0.30 HFTHF 2 52 52 3. Organometallic 6 0.30 HF.BN 2 45 4.8 45 7 0.30 HF.Pyr. 8 O - 4. Nicompound 8 0.30 HF.Acetone 4 76 4. 5. HF complex 0.075 millimole TEAL and 0.005 Nioct 0.005 millimole NiOct Et,0 - diethyl ether Table 7 BuO - dibutyl ether 50 THF - tetrahydrofuran Exp. BD:Ni* Polymer Yield DSW Mn BN - benzonitrile Pyr - pyridine No. mole ratio % at 4 Hrs. d/gm Osmotic t 0. - w 2 40 56 3.3 ND EXAMPLE V 55 3 100 7 3.3 137,000 4. 300 73 32 ND The procedure is the same as that used in Example *The amount of BD in the preformed catalysts varied and was 0, 3, 7.5 and 22.5 I except the catalyst concentrations were varied. Poly millinoles per 100 gm. of BD. merization time was 4 hours for all the experiments. Table 5 60

Exp. Millimole? 10 gm. BD Yield DSV EXAMPLE VIII No. TEAL NiOct HF.EtO Wt. diligm The procedure used is the same as that used in Exam l 0.07 0.005 0.25 63 2.6 ple VII except that the preforming conjugated diolefin 2 0.10 0.005 0.30 80 2.9 65 is myroene (7-methyl, 3-methylene, 1,6-octadiene) an 3 0.15 0.0075 0.45 86 2.8 isoprene dimer. 3,856,764 9 10 Table 8

Millimole per Exp. 10gm. BD PZn. Time Yield DSV No. Myrcene HF.Ether TIBAL. NiNaph Hours Wt.% di/gm .075 25 .10 0075 4 27 2 375 .25 .0 .0075 2 65 5.2 While certain representative embodiments and de ganic complex compounds of nickel; and in which the tails have been shown for the purpose of illustrating this 10 hydrogen fluoride complex is selected from the group invention, it will be apparent to those skilled in the art consisting of hydrogen fluoride-acetone complex, hy that various changes and modifications may be made drogen fluoride-tetrahydrofuran complex, hydrogen therein without departing from the spirit or scope of fluoride-dibutyl ether complex, hydrogen fluoride the invention. methanol complex, hydrogen fluoride-ethanol com What is claimed is: 15 plex, hydrogen fluoride-n-propanol complex, hydrogen 1. In a process for the polymerization of butadiene fluoride-isopropanol complex, hydrogen fluoride and butadiene in mixture with other diolefins to form diethylether complex, hydrogen-fluoride-phenol com polymers containing a high proportion of the butadiene plex, hydrogen fluoride-benzonitrile complex, and hy units in the cis-1,4 configuration comprising contacting drogen fluoride-water complex. at least one monomer from the group of butadiene and 20 5. The process according to claim 1 in which the butadiene in mixture with other diolefins under poly mole ratio of the organoaluminum compound/or merization conditions with a catalyst consisting essen ganonickel compound ranges from about 0.3/1 to tially of (1) organoaluminum compounds, (2) nickel about 300/1, the mole ratio of the HFC/organonickel compounds selected from the class consisting of nickel compound ranges from about 2/1 to about 300/1 and salts of carboxylic acids, organic complex compounds 25 the mole ratio of the HFC/organoaluminum compound of nickel, nickel tetracarbonyl, and mixtures thereof, ranges from about 0.2/1 to about 15/1. wherein the improvement comprises using (3) hydro 6. The process according to claim 4 in which the pre gen fluoride complexes (HFC) prepared by complexing ferred mole ratio of organoaluminum compounds/or hydrogen fluoride with a member of the class consisting ganonickel compound ranges from about 211 to about of ketones, esters, ethers, alcohols, and nitriles and 30 80/1; the preferred mole ratio of the HFC/or mixtures thereof in which the mol ratio of the organo ganoaluminum compounds ranges from about 0.4/1 to aluminum compound/nickel compound ranges from about 7/1. about 0.311 to about 300/1, the mol ratio of the 7. The process according to claim 4 in which the or HFC/nickel compound ranges from about 2/1 to about ganoaluminum compound is selected from the group 300/1 and the mol ratio of the HFC?organoaluminum 35 consisting of an aluminum trialkyl. compound ranges from about 0.2/1 to about 1571. 8. The process according to claim 1 wherein an or 2. The process according to claim 1 in which butadi ganoaluminum compound is utilized and the hydrogen ene-1,3 alone is employed. fluoride is prepared by complexing hydrogen fluoride 3. The process according to claim 1 in which the cat with an ether selected from the class of diethyl, tetrahy alyst is preformed in the presence of a conjugated di- 40 drofuran and dibutyl or a ketone selected from the olefin. class of dimethyl, or an alcohol selected from the class 4. The process according to claim 1 in which an or of methanol, ethanol, n-propanol, i-propanol, phenol, ganoaluminum compound is utilized; and in which the and cyclohexanol, or an aromatic nitrile selected from organo-nickel compound is selected from the group the class benzonitrile or water. consisting of nickel salts of carboxylic acids and or-. 45 >k k :k. k. k.

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