United States Patent (19) [11] 3,897,508 Tkatchenko (45) July 29, 1975 54) DOLEFIN DIMERIZATION 3,436,431 4/1969 Candlin et al................... 260/666 B 3,446,86 5/1969 Menapace et al.... ... 260/666 B 75) Inventor: Igor Tkatchenko, Pau, France 3,446,862 5/1969 Menapace et al............... 260/666 B 73) Assignees: Union Chimique Elf-Aquitaine, 3,526,672 9/970 Boyer - - - - - - A a a - ... 260/666 B Courbevoie; Institut Francais du 3,542,887 1 1/1970 Hillegass et al... ... 260/666 B Petrole desCarburants et 3,655,793 4/1972 Myers................ ... 260/666 B Lubrifiants, Rueil-Malmaison, both 3,660,342 5/1972 Duggan........................... 260/666 B of France Primary Examiner-Veronica O'Keefe (22 Filed Oct.... 10, 1971973 Attorney, Agent, or Firm-Ostrolenk Faber Gerb & 21 Appl. No.: 404,889 Soffen 30 Foreign Application Priority Data Oct. 10, 1972 France.............................. 72.35765 (57) ABSTRACT 52 U.S. Cl 260/666 B; 260/666 PY; 252/438 A process for the dimerization or codimerization of 51 ) int c a 9 coic 3700 diolefins in the liquid phase in an inert solvent solution 58 Field of search a 260/666B 666 PY using a catalyst comprising a complex obtained by re a A. A. R. a- A-4. R. R. a a a a a - s 252/438 acting the alkali metal or alkaline earth metal salt of tricarbonyl nitrosyl ferrate anion with a metallic halo 56 References Cited gen or pseudohalogen or complex thereof is disclosed. UNITED STATES PATENTS 13 Claims, No Drawings 3,377,397 4/1968 Maxfield ......................... 260/666 B 3,897,508 2 DOLEFN DIMERIZATION manipulation of non-toxic materials, ease in prepara tion, absence of expensive reducing agents in the sys BACKGROUND OF THE INVENTION tem, and optimum activity obtained at controllable The manufacture of 4-vinyl cyclohexene (hereinafter tempertures s between 40- 60° C. The catalyst of the called WCH) has been the object of substantial re 5 present invention also permits one to obtain VCH search for a long period of time. VCH is a material of from butadiene at practically quantitative yields. These prime interest because it can be easily dehydrogenated and other advantages of the present dimerization cata to produce styrene. lyst will be apparent to those of ordinary skill in the art It has been known for some time that the specific di from the following detailed description. merization of butadiene to VCH is possible by thermal 10 means but this procedure requires a high temperature SUMMARY OF THE INVENTION and the dimerization is slow. Additionally, a simulta This invention relates to dimerization catalysts and a neous polymerization occurs and competes with the de process of dimerization and more particularly to a pro sired Diels-Alder reaction. cess for the liquid phase dimerization or codimerization Utilization of catalysts have been recommended to 15 of diolefins with a catalyst comprising a complex ob improve the speed of the butadiene dimerization. The tained by reacting the alkali metal or alkaline earth catalytic systems comprising salts or complexes of metal salt of tricarbonyl nitrosyl ferrate anion with a nickel, iron or manganese with amine or phosphorus metallic halogen, pseudo-halogen or complex thereof. ligands and with reducing compounds, in particular or ganoaluminums, convert butadiene to a mixture of cy 20 DESCRIPTION OF THE PREFERRED clo- i.5-octadiene, VCH and 1,5,9-cyclododecatriene EMBODIMENTS in variable proportions according to operating condi The liquid phase diolefin dimerization of the present tions although the cyclo-1,5-octadiene is the predomi invention is characterized by use of a catalyst which is nant product. Thus, German Pat. No. 1,140,569 constituted by the reaction product of an alkali metal teaches that a nickel bis(acetylacetonate)-triphenyl 25 salt or alkaline earth metal salt of tricarbonyl nitrosyl phosphine - monoethoxydiethyl aluminum catalyst ferrate anion with a metallic halogen, pseudo-halogen yields VCH with only a 21% selectivity. or complex thereof, compound. Catalyst compositions giving VCH in a selective The alkali metal or alkaline earth metal salt of the tri manner from butadiene are known. Such systems are carbonyl nitrosyl ferrate anion is of the formula constituted by such metals as iron, ruthenium and co 30 M'Fe(CO)NO in which M is an alkali metal when balt which include a nitrosyl ligand in association with m is 1 and is an alkaline earth metal when m is 2. The a carbonyl ligand and/or 7t-allyl. Such systems are de compounds M'Fe(CO)NO) are known materials scribed in British Pat. Nos. 1,085,875 and 1,148,177 and can be prepared by methods described in the litera with iron dinitrosyl dicarbonyl, cobalt dinitrosyl dicar ture, for example, in R. D. King, Organometallic Syn bonyl and T-allyl iron nitrosyl dicarbonyl being recom 35 thesis, 1,167-168 (1965). Examples of usable salts in mended. However, these catalytic systems present a clude sodium and potassium tricarbonyl nitrosyl ferrate number of disadvantages. Their preparation requires and magnesium, calcium, strontium and barium bis(- two reaction steps starting from the metal carbonyl and tricarbonyl nitrosyl ferrate). they have a major disadvantage of being very volatile The halogen or pseudo-halogen compound is of the and having a significantly high toxicity. 40 formula MX in which M' is an element of Groups Further, when one uses these catalysts, the dimeriza I-A, II, III, IV, V, VI-B, VII-B or VIII of the Periodic tion reaction requires temperatures of at least 100° C. Table appearing on pages 60-61 of Lange's Handbook which involves a rapid deactivation of the catalyst. of Chemistry (Revised 10th Edition). The metals of Also, this catalyst can only be used after a more or less Groups II-A and VIII are particularly preferred. X is a long period of induction which decreases the economic 45 mono- or divalent anion and is a halogen such as fluo feasibility of the process. rine, chlorine, bromine and iodine or a pseudo-halogen French Pat. No. 1,502,141 describes a catalytic sys such as cyanide, sulfocyanide, isocyanate, nitrate, ni tem which has the advantage of accomplishing the di trite, sulfate, acetylacetonate, carboxylate, and the merization of butadiene at a temperature as low as like, and n is an integer from 1-6. As examples of these room temperature. This system is constituted by a hal 50 halogen and pseudo-halogen compounds there can be ide of iron dinitrosyl in association with a donor com listed: sodium chloride, magnesium chloride, calcium pound and a reducer. Butadiene is quantitatively trans chloride, strontium chloride, barium chloride, alumi formed to VCH at temperatures below 30°C. This dis num chloride, aluminum bromide, silver nitrate, fer advantage of this catalytic system is that it requires the rous acetylacetonate, and ferric acetylacetonate. use of an expensive reducer compound such as allyl 55 The complexes of MX are of the formula LMX magnesium bromide thereby decreasing industrial in in which L is a chalcogen or pnicogen and p is an inte terest in this catalytic procedure. ger of 1-6. Typical complexes include dichlorozinc bi French Pat. No. 1,535,936 teaches a catalytic system pyridine, dichlorotin bipyridine, dichloronickel bipyri using compounds such as dihalo-bis-(T-allyl dinitrosyl dine, dichloropalladium bipyridine, bis(pyridine) di iron) tin or germanium prepared in situ attemperatures 60 chloronickel, bis-(pyridine) dichloropalladium, bis(tri of the order of 40° C. for dimerizing butadiene. This phenylphosphine) dichloronickel, bis(triphenylphos catalytic system also requires the use of organometallic phine) dichloropalladium, bis(diphenylphosphino) compounds of tin or germanium which are expensive ethane) dichloronickel, bis(diphenylphosphino) eth and most often toxic. ane) dichloropalladium, and the like. The complexes The present invention remedies the disadvantages of 65 are prepared by mixing the compound MX with the the prior art. Thus, the catalyst of the present invention ligand L in an appropriate solvent, such as those de presents the following simultaneous advantages: easy scribed below. 3,897,508 3 4. The catyalyst of the present invention can be pre ing the recovery of VCH by a simple distillation with pared by mixing a suspension or solution of the alkali out having the need to separate solvents. metal or alkaline earth metal carbonyl nitrosyl ferrate The diolefins which can be dimerized with the de in an appropriate solvent with a solution or suspension scribed catalyst of this invention are very diversified. of MX or LMX in the same solvent. The mixture They can contain up to 10 or more carbon atoms and is heated from 30-70 C. and agitated for a time suffi can be conjugated dolefins such as butadiene, iso cient for reaction to occur, which can conveniently be prene, dimethylbutadiene and unconjugated diolefins about 1 hour. The ratio between the alkali metal or al such as norbornadiene. Codimerization can also be ac kaline earth metal ferrate and the MX compound or complished. The present catalytic system is especially one of its LMX complexes can vary over a wide 10 appropriate for the dimerization of butadiene in vinyl range of between 0.5 n/m and 5 n/m. It is preferable, cyclohexene with quantitative yield. however, that this ratio be equal to n/m which corre Another particular trait of the present invention is sponds to the stoichiometry of the reaction. that the catalyst will selectively dimerize the diolefin in The reaction which occurs to give the catalytic com a diolefin-monoolefin mixture. The monoolefin is un pound can be thought out as occurring according to the 15 changed after the dimerization process and separation following reaction scheme: of the dimer and the olefin is very easy.