[1]3 @ 4 2 0 @ 8 9 9 United States Patent Office Patented Jan. 7, 1969 1 3,420,899 PROCESS FOR THE CATALYTIC PREPARATION OF CYCLODODECATRIENTES-1,5,9 FROM CONJUGATED DIOLEFINS AND CATALYSTS THEREFOR 5 Carlo Longiave, Renato Castelli, and Alberto Andreetta, Novara, and Angelo Garberi, Cilavegna, Pavia, Italy, assignors to Montecatini Edison, S.p.A., Milan, Italy No Drawing. Continuation of application Ser. No. 293,262, July 8, 1963. This application July 25, 10 1967, Ser. No. 655,962 Claims priority, application Italy, July 9, 1962, 13,540/62 U.S. Cl. 260-666 11 cums Int. Cl. C07c 3160, C07c 3110 15 ABSTRACT OF THE DISCLOSURE T'he present invention relates to a catalytic process for the preparation of 1,5,9 cyclododecatriene. According to the present invention, the ring of the conjugated diolefin 20 is closed by using a catalyst consisting of a titanium halide selected from the group consisting of tri- and tetravalent halides complexed with an organic nitrogen basic compoi.ind and an alkyl aluminum dihalide complexed with a Lewis base. The catalyst of the present invention is 25 soluble in the reaction solvent, acts in a homogeneous phase, and appears extremely stereospecific in the cyclic trimerization of the conjugated diolefins (b utadiene-1,3, isoprene, piperylene, etc.). It consists of four essential 30 components: (A) A titanium halide; (B) An organic nitrogen-containing substance to form the complex with the titanium halide; (C) An alkyl aluminum dihalide; (D) An electron-donor substance of the Lewis base 35 type to form a complex with the organic aluminum halide. The ratio of the complexing substance to the organic aluminum halide must be such that there remains in the 40 reaction solution an amount of uncomplexed aluminum compound equal to at least 1.5 grams per liter of solution. This application is a continuation of Ser. No. 293,262 filed July 8, 1963, and now abandoned. 1 45 This invention relates to catalytic processes and more particularly to a process for the preparation of - cyclododecatriene-1,5,9 and of substituted cyclodod ecatrienes-1, 5,9 by cyclic trimerization of the conjugated diolefin in the presence of catalysts. 50 Italian Patents Nos. 568,727, 606,606, 602,501, and 614,050 described processes for the preparation of cyclododecatrienes from conjugated diolefins with the aid of catalytic systems consisting of titanium halides and alkyl aluminum halides, chromium halides and alum'mum 55 alkyls, titanium or chromium halides and altiminum hydride or complex metal hydrides. Italian Patent No. 628,333 teaches, for ring closure of diolefins to yield cyclododecatrines, the use of catalysts 60 obtained @from titanium halides and alkyl aluminum halides to which compounds containing in the molecule a semi-polar double bond (sulfoxides, a:minoxides, nitrones) are added. The catalysts described in all cited patents are of heterogeneous nature and therefore promote, together with 65 the formation of cyclododecatriene, the formation of byproducts (1,5-cyclooetadiene-3-vinyl-cyclohexene, higber homologues of cyclododecatriene, open chain polymeric compounds of butadiene). The presence of byproducts, 70 besides lowering the yields, renders difficult the - recovery and purification of the cyclododecatrienes. Italian Patent 2 628,333 teaches a process wherein the formation of linear, solid polymers is reduced, but not completely eliminated. Copending U.S. patent application Ser. No. 181,181, filed on Mar. 3, 1962, describes a process for ring closure of conjugated diolefins to yield cyclododecatrienes, eliminating completely the formation of linear solid high polymers and reducing the formation of such liquid polymers to vqry low amounts. The process is characterized by the use of a catalyst soluble in the reaction solvent, which is obtained by mixing an organic aluminum halide of the type AIR2X (wherein R is a hydrocarbon radical and X is a halogen) with a complexed titanium halide that is soluble in the reaction solvent. The complex is formed with organic nitrogen-containing substances (primary aliphatic amines, cycloaliphatic amines, heterocyclic compounds containing at least one nitrogen atom in the ring, etc.). The above homogeneous catalyst is highly stereospecific since it directs the polymerization almost completely to the formation of the cyclic trimer, particularly in the case of butadiene, to the formation of cyclododecatriene-1,5,9. However, it presents two inconveniences: (1) a rather low rate of reaction, requiring long contact time (at least 6 hours) to obtain a good conversion of the monomer to the cyclic trimer; and (2) low stability; it loses its kinetic and stereospecific activity, if aged for some time after its preparation. It is an object of this invention to provide a catalyst for the ring closure of conjugated diolefins to yield cyclododecatrienes. It is another object of this invention to provide a process for the almost exclusive formation of cyclic trimers at high rates. It is a further object to provide a catalyst that is stable with regard to its kinetic qualities and with regard to its stereospecificqualities. It is a further object of this invention to provide processes for the utilization of such catalysts. We have now found a catalyst for the ring closure of conjugated diolefins to yield cyclododecatrienes which, beside directing the reaction to almost exclusive formation of the cyclic trimers, permits effectin@ the reaction at high rates with nearly total conversion in time periods that are about one tenth of those described in the above-mentioned copending earlier U.S. patent application. Furthermore, the new catalyst is stable and may be prepared many hours or days before use. It may be stored at room temperature or even at higher temperatures (80-100' C.) without losin- its initial activity. The only precaution regarding its stability is that it rnust be stored away from contact with air or moisture. The catalyst of our present invention is soluble in the reaction solvent, acts in a homogeneous phase, and appears extremely stereospecific in the cyclic trimerization of the -conjugated diolefins (butadiene-1,3, isoprene, piperylene, etc.). It consists of four essential components: (A) A titanium halide; (B) An organic nitrogen-containing substance to form the complex with the titanium halide; (C) Alkyl aluminum dihalide; (D) An electron-donor substance of the Lewis base type to form a complex with the organic aluminum halide. As titanium halides there may be employed both the trivalent and the tetravalent titanium halides. The trivalent halides, and especially titanium trichloride, furnish higher yields of cyclododecatrienes and are preferred. Other suitable halides are titanium tetrachloride, titanium tribromide, titanium tetraiodide. The complexing nitrogencontaining substance for the titanium halide may be either a primary amine or a heterocyclic compound containing a nitrogen atom in the ring. Among the primary amines. they n-iay be aliphatic, cycloaliphatic or arylaliphatic. The primary aliphatic amines should have at least 4 carbon
[2]3 atoms in the main chain. Such amipes include n-hexylamine and nonylamine. Other amines that have been found to dissolve the titanium halides satisfactorily and to yield stable complexes, include primary 5,5-dimetbylhexylamine and primary 3,5,5-trimethylhexylamine. Among the arylaliphati-- amines with the ami-iie group attached to the aliphatic -roup, there may be menlic)ned deltaphenylbutylamine. Satisfactory complexirig heterocyclic con-lpounds i@iclude pyridine,- piperidine, qliinoline, and hydrogenated qtiinoline. In the preparation of the titanitim comi)lex, the organic nitrogen-containing compgund is empioyed in proportions of 1-10 mols per mol of titai-iitim halide. The titanium complex is prepared by reacting the titaniuin halide with the nitrogen compound alone or in an inert solvent. The solution of titanium salt ii 'Lhe amine may be prepared in the following manner. In a perfectly dry and de-aerated 500 cc. flask are introduced 2 grams of titanium trichloride (0.013 mol) and 10 grams of primary 5,5- dimethylhexylamine (0.078 mol). The coiitents of the flask are n3ixed and heated for about o-@ie hour at 80' C. A blue-black-colored mass forms, to which are added 300 cc. of anhydrous benzene. After stirring 'lor folr hours, a limpid solution is obtained which is -reer,.-brown-colored and in which is dissolved practically all o'l the titanium (about 0.042 mol/l. of titanitim). This catalyst coniponent is very stable, provided that it is stored under anhydrous conditic)ns in the absence of air and moisture. The alkyl aluminum dihalide has the general formula AIRX2 wherein R is alkyl and X is a halogen. The alkyl aluminum dihalide may also be erndloyed admixed with alkyl aluminum monohalide having the formula AIR'2X (wherein R' is an alkyl, equal to or different from R) provided that the compotind AIRX2 forms at least 50% by mols of the mixture. The alkyl aliiminum halide may be complexed with the Lewis base before or after it is reacted with the soluble titanium complex described above. The presence of the electron-donor group in the catalyst appears to be essential; in the absence of this donor group (Lewis base), the catalyst forms, besides cyclododecatriene. substantial amounts of other linear or cyclic polymers of the starting diolefins. Such other polymers decrease the yield of the process. However, when the Lewis base is present, the catalyst is extremely stereospecific and promotes the polymerization of the olefins to the formation almost exclusively of cyclic trimers. The yields are higher than 90% in the case of butadiene. As complexin.- compounds of the organic altiminum halide there are employed organic Lewis bases, i.e. organic substances which contain an atom capable of releasing a pair of electrons. Suitable bases include the aliphatic and aromatic aldehydea, which may be saturated and unsaturated, and include such compounds as acetaldehyde, propionic aldehyde, butyraldehyde, acrolein, benzaldehyde. Another class of Lewis bases are the ethers, preferably the satiirated aliphatic ethers including diethyl ether, dipropylether, methylpropylether. Ai3other group of Lewis bases are the esters, preferably those from aliphatic or aromatic saturated acids and aliphatic monovalent alcohols, such as ethyl acetate, ethyl butyrate. Another class of Lewis bases suitable in this inve-@ition are the amines, such as the primary alkylamines, including ethylamine, isopropylamine, hexylamine; the secondary alkylamines, such as dimethylamine, d-ethylamine; and the tertiary alkylamines, such as trimethylair@ine, triethylamine; and the arylamines, including aniline and diphenylamine. A further class of Lewis bases suitable for this invention are heterocyclic substances, such as pyridine, isoqtiinoline, f uran, thiophene. The ratio of the complexin.- substance to the organic aluminum halide must be such that there remains in the reaction solution an amount of uncomplexed aluminum compound equal to at least 1.5 grams per liler of solution. Solvents may be employed for the catalyst. They must be inert with respect to the organometallic complexes a@id must be capable of dissolvinq the entire catalyst cOm32420)899 4 plex. Among suitable solvents are the aromatic and cycloaliphatic hydrocarbons; the halo derivatives of the aromatic hydrocarbons. The paraffinic solvents are less suitable due to the low solubility of a catalyst in this class of solvents. However, they may be used, nevertheless, in admixture with aromatic solvents such as benzene and "olue--,ie. The mononiers that are most satisfactorily converted inlo the cyclic trimers by the catalyst and process accordin-, to this invention are conjugated diolefins, such as 10 bLitadiene-1,3; isoprene; and piperylene. The diolefins may be used either pure or adinixed with other hydrocarbons, such as alkanes and/or alkenes. It is possible to use for the production of cyclododecatrienes, the mixture of hy@ 15 drocarbons C4 obtained from petroleum cracking or from the dehydro-enation of butane or of butenes. Such latter mixtures contain, besides butadiene, isobutane, butane, btitene-1, and bu,ene-2. In general, the catalyst is prepared by introducing it 20 fnto the solvent, first the alkyl altiminum halide, then the electron-donor compound, and finally the solution of the complex titanium halide with the nitrogen compound. This particular catalyst does not require much of the titanitim halide, and generally from 0.1 to 10 millimols 25 per liter of reaction mixture is sufficiert. The general preferred range is from 0.3 to 3 millimols/liter. The amounts of the organo-aluminum compound that are necessary in the catalyst composition are substantially higber than those of the titaniurn compound and should 30 range from 10 to 40 millimols/liter of reaction mixture. Hi.-her amounts may be used but there is no particular advantage. The electron-donor compound for complexing the aluminum compound in a coordination complex is preferably used in 10-30% by mol of the hydrocarbyl 3,5 aluminum dihalide. The concentration of diolefins in the reaction system may be varied with-n rather wide limits. Generally, concentrations of 20-800 grams per liter of solvent, and preferably 50- 250 grams per liter of solvent are used. 40 The operative ran-e of temperatures is between 0 and 150' C., and it is @generally preferred to operate this process between 50 and 100' C. The pressure is autogenous to the reaction conditions. The time necessary to complete the reaction is quite short and depends upon the amount of catalyst, the concentration of monomer, 45 and the temperature at which the reaction is run. In a batch operation of cyclic trimerization of butadiene, nearly quantitative yields of cyclododecatriene are obtained in periods varying from 10 minutes to I hour, by operating irl benzene with a catalyst according to this invention con50 sisting of titanium trichloride complexed with primary 5,5-dimethylhexylamine, and ethyl aluminum dichloride complexes with diethyl ether. The catalyst of this invention and the process based thereon are particularly suitable for a continuous opera55 tion which is performed in one or more reactors that are thermostatically controlled and are each provided with a stirrer; into the reactors are introduced continuously the solvent, the catalyst and the monomer to be cyclized. When the reaction is completed, the reacted soltition is 60 treated with a small ar.,lount of alcohol or water to destroy the catalyst. The solvent is then recovered by fractional distillation initially at atmospheric pressure until all the solvent is distilled and the unreacting hydrocar-bons aecompanying the diolefin are removed. Then the pressure 65 in the distillation apparatus is reduced and the pure cyclododecatriene is recovered. The cyclododecatriend may also be recovered by steam distillation. In the case of the cyclization of butadiene, cyclododecatriene-1,5,9 is re70 covered, for example, by distillation at 100' C. under a residual pressure of 10 mm. Hg. The cyclododecatrienes that are obtained from butadiene-1,3, according to the process of this invention, consist essentially (above 90% ) of a stereoisomer: cis75 trans-trans and of small amounts (1-8%) of the trans-
[3]3)4202899 5 trans-trans-stereoisomer. The two stereoisomers have been identified by means of their I.R. spectra and both boiling and melting points (I 00' C./ 1 1 mm. Hg and - 18' C. in the case of cis-trans-trans isomer; 95' C./13 mm. Hg and 34' C. in the case of the transtrans-trans isomer). 5 The following polymerization examples are intended to illustrate our invention -without any limitation to the scope thereof intended. EXAMPLE 1 2.5 g. of ethyl aluminum dichloride (19.7 millimols), 10 0.290 g. of diethyl ether (3.94 millimols) and 300 cc. of anhydrous benzene are introduced into an inox steel 1800-cc. autoclave that is carefully dried and deaerated, and is provided with a stirrer and a thermostat. 400 cc. Of 15 a benzene solution of the complex titanium trichlorideprimary 5,5-dimethyl-hexylamine containing 0.0774 g. of titanium trichloride (0.5 millimol) are then added; ratio N/Ti=6. The temperature is raised to 50' C. while stirring, and 105 g. of Rubber Grade butadiene-1,3 are introduced. The stirring and the temperature are main- 20 tained for one hour. Then 30 cc. of methyl alcohol are added into the autoclave to destroy the catalyst. The reacted solutioti is discharged from the autoclave, and treated with HCI to eliminate the catalyst residue. Two layers are obtained; the upper one, concentrated under 25 vacuum, leaves as a residue 103 g. of an oil that by fractional distillation yields 99 g. of cyclododecatriene1,5,9 (yield=94.2%). EXAMPLE 2 30 The test is carried out in the same apparatus and in the same manner as described in Example 1. An amount of 2.5 g. equimolar mixture of diethyl aluminum monochloride and ethyl aluminum dichloride is employed, maintaining unchanged the amount of the other substane-,s 35 forming the catalyst. The temperature is raised to 80' C., and 140 g. of "Rubber Grade" butadiene (in liquid phase) are introduced. The reaction is continiied for 45 minutes. Then 40 the catalyst is destroyed with 50 cc. of methyl alcohol, .@nd the crude is discharged from the autoclave. The solution is washed with diluted RCI, the solvent is evaporated under vacuum. Obtained are 136 g. of oil which is subjected to fractional distillation under vacuum. 132.5 g. of cyclododecatriene-1,5,9 are recovered - (y;eld= 45 94.6%), of which 91% consistof the cis,trans,trans-stereoisomer and 9% of the trans,trans,trans-stereoisomer. Solid polymers are not obtained. EXAMPLE 3 50 The method is performed as in Example 2, except that 2.5 g. of a mixture of diethyl alumi-tium chloride and ethyl aluminum dichloride containing 80% of ethyl aluminum dichloride is used, employing n-butyl other (0.51 g.=3.94 mm.) as a complexing agent of the aluminum- 55 organic component. The titanium complex is used in the amounts indicated above. The temperature of the autoclave is raised to 60' C., and 80 g. of "Rubber Grade" butadiene are introduced 60 into the liquid phase. After 30 minutes the reaction Is stopped by destroying the catalyst with 50 cc. of methanol, and the reaction product is discharged from the autoclave. After the usual treatment for purification, concentration and rectification of the oil, 72.9 g. of cyclododecatriene-1,5,9 are recovered (yield=91%). Solid po y- 6,5 mers are not formed. EXAMPLE 4 Charged into the autoclave are 2.5 g. of ethyl aluminumdichloride (19.7 mM.) dissolved in 300 cd. of anhydrous 70 toluene, and 0.23 g. of pyridine (2.95 mM.) dissolved in 50 cc. of toluene. Then 350 cc. of toluene solution of the complex titanium trichloride/primary trimet-hyl-hexylamine-3,5,5 containing 0.0774 g. of titanium trichloride (0.5 mM.); ratio N/Ti=6 are added. 75 6 I IO g. of "Rubber Grade@' butadiene in liquid phase are introduced and the temperature is raised rapidly to 70' C. The stirring and the temperature are maintained for 90 minutes: The catalyst is destroyed; the reaction product is discharged from the autoclave, and is submitted to the usual treatments for the recovery of cyclododecatriene. Obtained are 106 g. of -eyelodo decatriene-1,5,9 (yield =96.4%). EXAMPLE 5 This test was carried out employing butadiene in mixture with other hydrocarbons. The composition of the mixture was as follows: Propane --------------------------- pereent-- 0.1 P ropylene -- --------------------------- d o -- -- 0. 1 Is obutane -- --------------------------- d o -- -- 1. 6 nButane -- ---------------------------- d o -- -- 1 2.4 B utene-1 -- ---------------------------- d o -- -- 3 6.7 B utene2 tr ans ------------------------ d o -- -- 1 2.4 B utene2 ci s -------------------------- d o -- -- 5. 2 Butadiene-1,3 -------------------------- do ---- 31.5 A cetylene compounds ------------------ p. p.m-- <20 Water -- ----------------------------- p. p.m-- 150 3 g. of ethyl aluminum dichloride (23.6 mM.) in 500 ,. of anhydrous benzene and 0.22 g. of diethyl ether (2.95 mM.) are introduced into the atitoclave. Then 320 g. of the hy&ocarbon mixture containing butadiene are added, and the temperature is raised to 65' C. 0.0774 g. of titanium trichloride (0.5 mM.) in the form of the complex titanium trichloride/5,5-dimethyl-hexylamine, that are dissolved in 200 cc. of benzene, are introduced by use of a nitrogen pressurized cylinder. The stirting and the temperature are maintained for two hours and then the catalyst is destroyed with 50 cc. of methanol. The reaction product is discharged and submitted to the usual operations of purifying and rectifying for the recovery of cyclododecatriene, 89 g. of cyclododecatriene-1,5,9 are obtained, corresponding to a yield of 88% in respect to butadiene. Solid polymers are not obtained. EXAMPLE 6 Example 5 is repeated using the same amounts of reactants but varying the sequence of the charge. The reactants are introduced into the autoclave in the following sequence: ethyl aluminum dichloride in benzene, diethyl ether and solution of the complex titanium trichloride/ amine; the temperature isthermostatically set at 65' C., and then the hydrocarbon mixture containing butadiene is introduced into the autoclave. The reaction is continued for 90 minutes. After carrying out all recovery operations, 87 g. of cyclododecatriene-1,5,9 are obtained, corresponding to an 86% yield from the introdiiced butadiene. There is no formation of solid polymers. EXAMPLE 7 The preparation of cyclododecatriene is carried out by opetating in a continuous pilot plant. The plant consists of: (a) Two tanks containing a benzene solution of the catalyst. The tanks are iised alternately. Each contains a charge sufficient for 12 hours. The catalyst is obtained from ethyl aluminum dichloride, diethyl ether, titanium trichloride, and 5,5- dimethylhexylamine. The catalyst solut'on has the following composition: G./I. benzene Titanium trichloride -------------------- 0.1305 Amine ------------------------------- 0.652 Ethyl aluminum dichloride -------------- 5.6 Ether -------------------------------- 0.495 (b) Two tanks containing a benzene solution of butadiene. Each tank has a volume sufficient for a run of 15 hours. The butadiene solution has a concentration of 0.425 g. of C4H6/1. benzene.
[4]3,420,899 7 (e) Two reactors each having a volumetric capacity of 38 liters, provided with a stirrer with arms, and a jacket for thermostatic temperature setting. The reactors are connected in series. The reactants are pumped at the base of the first reactor, are drawn off from the head and enter at the base of the second reactor. At the outlet of the second reactor, a small amount of methanol sufficient to destroy the catalyst is added to the reactor product. The two reactors are maintained at 65' C. by hot water circulation in the jacket. The hourly amounts of reactants pumped are as follows: (1) 7.5 liters of a beizene solution of catalyst containing: G. Titanium trichloride ------------------ 0.98 Amine ----------------------------- 4.9 Ethyl aluminiim dichloride ------------ 42 Ether ------------------------------ 3.72 (2) 7.4 liters of a benzene solution of butadiene containing 1.87 kg. butadiene. The total reaction time is 5 hours. The solution obtained after the destruction of the catalyst is washed with a soda solutioii to eliminate the acidity caused by catalyst decomposition, and is sent to a rectifying column. First the solvent is distilled at atmospheric pressure and then cyclododecatriene is distilled under vacuum at a residual pressure of 10 mm. Hg. The r-un of the plant lasts 144 hours employing a total of 269.3 kg. of butadiene-1,3. At the end of the operations there are obtained 250 kg. of cyclododecatriene-1,5,9 (yield=93%), consisting of 96% of cris,trans,trans-stereisomer, and 4% of trans, trans,trans-stercoisomer. There is no forniation of solid polymers. EXAMPLE 8 Used is an inox steel autoclave with stirrer and thermostat, previously dried and deaerated by means of repeated vacuum operations and washin.- with nitrogen. Introduced are 2.8 g. of ethyl aluminum dichloride (22 millimols) and 0.325 -. of diethyl ether (4.4 millimols) dissolved in 600 cc. of anhydrousbenzene. Then charged into the autoclave are 100 cc. benzene containing 0.1 g. titanium tetrachloride (0.527 m,illimol) complexed with primary 3,5,5-trimethylhexylamine (N/Ti=6) The complex of titanillim tetrachloride with the arnine is prepared by mixing, at room temperature, i-,ito a benzene solution of titanium tetrachloride, the necessary amount of 3,5,5-trimethylhexylamine. A limpid orange-red solution is obtained. The autoclave is heated to 65' C. Then 110 g. "Rubber Grade" butadiene are introduced into the ai.itoclave by evaporating the butadiene from the vessel in which it was previously weighed. The absorption of butadiene is very rapid and, after one hour, the reaction is practically completed. The catalyst is destroyed by introducing into the autoclave 50 cc. methanol, and the reaction product is dis-charged. After the usual operations to eliminate the catalyst and to evaporate the solvent, 109 g. of oils are obtained, and 98 g. of cyclododecatriene-1,5,9 (yield= 89.1 % are recovered by frictional distillation under vacuum. There is no formation of solid polyniers. EXAMPLE 9 Example 8 is repeated carrying out the reaction at 54' C. Butadiene is introduced into the atitoclave throu.-h a pipe into liquid phase. 120 g. of butadiene are charged. After 50 minutes the re@,,ction is stopped by addin.- 30 cc. methanol. After the usual treatiiients to eliminate the 8 wherefrom 102 g. of cyclododecatriene-1,5,9 are recovered (yield=85%). EXAMPLE 10 Into the autoclave of Example 8 are charged 600 cc. of a benzene solution containing 2.8 g. of ethyl aluminum dichloride (22 millimols) and 0.325 g. of diethyl ether (4.4, millimols). Then 100 cc. of benzene containing 0.0774 g. (0.5 millin-iol) of titanitim trichloride com10 plexedwith primary 3,5,5-trimethylhexylamine (N/Ti=6) and 109 g. isoprene are introduced. The reactor content is heated to 65' C. Stirring and temperature are main15 tained for 6 hours. The reaction is stopped by adding 30 cc. methanol into the reactor. The reaction product is discharged from the autoc-lave and treated with an excess of methanol to coagulate the polymer, if present. 20 g. of a semi-solid, sticky polymer are obtained. The 20 liquid is evaporated, and 70 g. of oil are left as a residue and are subjected to fractional distillation under vacuum. Thus recovered are 42.2 g. (yield=39.6% ) of a limpid, colorless liquid that distills at 95-96' C. under a residual pressure of 4 mm. Hg, consisting of 1,5,9-trimethyl1,5,9- 25 cyclododecatriene. EXAMPLE 11 The apparatus described in Example 8 is used. 600 cc. of a benzene solution containing 2.5 g. of AI(C2H5)CI2 30 (19.7 millimols) and 0.29 g. of ethyl ether (3.94 millimols) are charged in the autoclave. 100 cc. of benzene containing 0.278 g. of Til4 (0.5 niillimol) complexed with primary 3,5,5-triinethylhexylamino (N/Ti ratio=6) are then introduced. 35 The complex of Til4 with the amine is prepared by mixing the two reactants in the pure state and in the suitable ratio, and then adding benzene in order to dissolve the complex thus formed. The solution of the complex is clear yellowish; when added to the AI(C2H5)CI2 solu40 t-ion it gives an orange-red color. 101 g. of "Rubber Grade" butadiene in the liquid phase are introduced and the temperature of the autoclave is quickly brought to 60' C. After 3 hours the reaction is practically completed and the catalyst is destroyed by introducing 50 cc. methanol into the autoclave. Thereaction 45 product is then discharged. After the usual operations for el@in-iination of the catalyst and evaporation of the solvent, 80 g. of oil are obtained from which, by fractional distillation under vacuum, 66.3 g. of 1,5,9-cyclododecatriene (yield=65.5%) 50 are separated. 13 g. of a solid polymer are obtained, EXAMPLE 12 55 The apparatus of Example 8 is used, and 600 cc. of benzene solution containing 2.5 g. of AI(C2H5)CI2 (19.7 millimols) and 0.29 g. of ethyl ether (3.94 millimols) are charged into the autoclave. 100 cc. of benzene containinig 0.0774 g. of TiCI3 (0.5 60 millimol) complexed with piperidine (N/Ti ratio=6) are then introduced. The complex of TiCI3 with piperidine is prepared by mixing the two reactants in the pure state in the suitable ratio (a heat development is noted) and then adding benzene to dissolve the complex thus formed. 65 The solution of the complex has a dark brown color, and when added to the AI(C2H5)CI, solution a light green color is noted. 10@3 g. of "Rubber Grade" butadiene in the liquid phase are introduced and the temperature is quickly brought to 70 60' C. After I hour and 45 minutes the reaction is completed. The reaction is stopped by addition of 50 cc. methanol. The iisual operations then produce 102 g. oil from which 89 g. of 1,5,9-cyclododecatriene (yield of 86.5%) are catalyst residue and the solvent, 109 g. oil are obtained 7,5 separated by fractionated distillation.
[5]3,420,899 9 EXAMPLE 13 By operating as in Example 1, 3.06 g. of aluminum isobutyl dichloride (19.7 millimols) are -used instead of AI(C2H5)CI2- 105 g. of "Rubber Grade" butadiene are then introduced. After 3 hgurs and 30 minutes the re- 5 action is practically completed. By operating as usual, 95 g. of oil are obtained from which 79 g. of 1,5,9- cyclododecatriene (yield 75.2%) are recovered by distillation under vacuum. No solid polymer is present. 10 We
