DE1080547B - Process for the production of optionally methyl-substituted cyclododecatriene- (1, 5, 9) - Google Patents

Description

Process for the preparation of optionally methyl-substituted Cyclododecatriene- (1,5,9) It is known from Belgian patent 551180, that one 1,3-dienes with the aid of catalysts derived from aluminum alkyl halides and titanium halides are formed, can polymerize to 1,5,9-cyclododecatrienes.

Following the procedure of Belgian patent 564175 one obtains Cyclododecatriene- (1,5,9) by trimerization of 1,3-dienes in the presence of Catalysts made from aluminum alkyls and chromium chlorides.

In both processes, the yield is up to 80% of theory, the remaining raw material is mainly used in high molecular weight, rubbery products converted.

These swell in the solvents used, so that the Reaction mixture transformed into a highly viscous, difficult to handle mass, whereby in particular, the continuous implementation of the implementation is made more difficult.

It has now been found that methyl-substituted substances can be used Cyclododecatriene (1,5,9) by catalytic trimerization of butadiene (1,3) or isoprene, advantageously in the presence of a solvent and in an inert gas atmosphere, in very good yields if one consists of an organoaluminum compound, either three organic radicals each bonded via a carbon atom or two contains such radicals and a hydrogen atom, furthermore from a non-identical Compound of the general formula AlR'R "R" ', in which R' is an alkyl radical, R "'is a Alkyl or alkoxy radical or a halogen atom and R "'an alkoxy radical or a halogen atom mean, and from a titanium compound of the general formula Ti (R "'), in which R"' has the same meaning as the catalyst system obtainable in the preceding formula used.

Surprisingly, the new process gives yields of optionally methyl-substituted cyclododecatriene (1,5,9), which is up to 90 O / o the theory. A particular advantage of the new process is that that the proportion of high molecular weight, rubbery by-products remains low, what for the continuous implementation of the process is advantageous.

The solvent used is advantageously aliphatic hydrocarbons, such as pentane, hexane, heptane or mixtures thereof, aromatic hydrocarbons such as Benzene, toluene and xylene, as well as chlorinated hydrocarbons such as chlorobenzene and dichlorobenzene.

The catalyst system consists of three components.

Of the organoaluminum compounds, the three have one carbon atom each Bound organic radicals or contain two such radicals and a hydrogen atom, are primarily the dialkyl aluminum hydrides, such as diethyl aluminum hydride or Diisobutylaluminum hydride, and the aluminum trialkyls, such as aluminum tripropyl, aluminum triisobutyl, Diisobutylaluminumhexyl and especially aluminum triethyl.

Of the aluminum compounds of the general formula A1R'R "R" 'are for example the dialkyl aluminum chlorides such as diethyl aluminum chloride, dipropyl aluminum chloride and diisobutyl aluminum chloride, alkyl aluminum dichlorides, such as alkyl aluminum dichloride, Butylaluminum dichloride, dialkoxyaluminum alkyls such as diethoxyaluminium ethyl and Dipropyloxyaluminumethyl, alkoxyaluminum dialkyls such as ethoxyaluminum diethyl and Propyloxyaluminium diethyl, also alkoxyalkylaluminum halides, such as ethylethoxyaluminum chloride and propyl ethoxyaluminum chloride.

Used as titanium compounds of the general formula Ti (R "') it is advantageous to use titanium tetrahalides, in particular titanium tetrachloride, and also titanic acid esters lower alcohols such as titanium tetramethylate and titanium tetraethylate.

But also mixed titanium haloalkoxy compounds, such as diethoxytitanium (IV) dichloride, are usable.

For the reaction to succeed, it is important that the components from which the catalyst is produced, are present in certain proportions. If you use z. B. as an aluminum organic compound an aluminum trialkyl, as Aluminum compound of the general formula AlR'R "R" 'a monoalkylaluminum dichloride or a dialkoxyaluminum alkyl and as a titanium compound of the general formula Ti (R "'), Titanium tetrachloride or a titanium acid tetraalkyl ester should be the molar Amounts of the substances mentioned expediently in the approximate ratio Ti (R "') 4: AlR'R" R "' : organoaluminum compound = a: b: (a + b) are located, where the value of the quotient a: b is advantageously between 1: 1 and 1: 6. If, on the other hand, one uses under the otherwise the same conditions as the aluminum compound of the general formula AlR'R "R" ' Dialkyl aluminum chloride or an alkoxyaluminum dialkyl so is a molar ratio of the components mentioned such as a: b: a is recommended. Of the Here, too, the value of the quotient a: b is expediently between 1: 1 and 1: 6.

As a rule, the catalyst is used in such a way that the sum of the Amounts by weight of the individual components about 1 to 10 01 ,, based on the 1,3-diene, matters.

Since the catalyst is very sensitive, the process is carried out using absolute solvents and in the atmosphere of an inert gas, like nitrogen or argon.

The process can be carried out within a wide temperature range, between -50 and +1500 G. It is advantageous to work at 40 to 70 " C.

The reaction is usually carried out under atmospheric pressure, however, sometimes, especially when using low-boiling starting materials and at high reaction temperatures, higher pressures, for example 2 to 10 at, necessary.

To carry out the process, the catalyst is first provided ago, advantageously by adding the individual components in any order to the solvent that is desired for the later reaction. The resulting one The starting material is then fed to the suspension. The implementation is exothermic, through Cooling and appropriate supply of the 1,3-diene becomes the desired reaction temperature adhered to. It is advantageous to stir after the feed of the starting material has ended a while to complete the implementation. The catalyst system is destroyed expediently by adding a small amount of a lower alcohol and falling with it Polybutadiene by adding a suitable solvent such as acetone.

The reaction products are advantageously by distillation of the optionally obtained by washing out the mixture freed from inorganic constituents.

The starting material is used to carry out the process continuously and the suspension of the catalyst is expediently cocurrent and the reaction mixture operates in the manner described.

The parts mentioned in the following examples are parts by weight.

Example 1 In 80 parts of benzene, 1.14 parts of titanium tetrachloride, 0.7 parts of aluminum triethyl and 2.2 parts of diethylaluminum chloride are added. In the The resulting brown suspension is a brisk stream of butadiene (1,3) with stirring initiated. The temperature rises rapidly and the mixture is kept by external cooling to 500 ° C. Within 2 hours, 132 parts of butadiene (1,3) are taken up. The mixture is stirred for a further -4 hours at 30 to 400 ° C. and the catalyst is destroyed Add some methanol. The mixture is poured into 300 parts of acetone, whereby 10 parts, corresponding to 80%, of the butadiene used, as rubbery polybutadiene be felled. The acetone is washed with it Water out and obtained by distillation of the remaining mixture 118 parts, corresponding to 900 /, the theory, cyclododecatriene- (1,5,9) from boiling point bp 12 95 "C.

Example 2 1.14 parts of titanium tetrachloride are dissolved in 90 parts of benzene and the solution is carefully mixed with a mixture of 1.7 parts of aluminum triethyl and 1.1 parts of ethyl aluminum dichloride. Proceed as described in Example 1, and receives 11,010 polybutadiene and 8601, cyclododecatriene- (1,5,9).

Example 3 Dissolve as described in Example 1 in 100 parts Chlorobenzene in succession 1.14 parts of titanium tetrachloride, 1 part of diisobutylaluminum hydride and 2.9 parts of diethyl aluminum chloride. Proceed as in example 1 and receives 801, of the converted butadiene as polybutadiene, 840 /, as cyclododecatriene (1,5,9) and 801, as brown oil.

Example 4 Dissolve as described in Example 1 in 100 parts Benzene in succession 1.14 parts of titanium tetrachloride, 2.2 parts of diethylaluminum chloride and 0.7 part of aluminum triethyl. The brown solution is then made with 30 parts of isoprene added and the reaction mixture heated to 50 to 600 G for 15 hours with stirring. Proceed as in Example 1 and obtain 600% of a mixture of isomeric Trimethylcyclododecatriene- (1,5,9) with a boiling point of bp, 120 to 124 "C and the refractive index n2o0 = 1.5128.

Claims (1)

PATENT CLAIM Process for the production of optionally methyl-substituted Cyclododecatriene- (1,5,9) by catalytic trimerization of butadiene- (1,3) or Isoprene, advantageously in the presence of a solvent and in an inert gas atmosphere, characterized in that one of an organoaluminum compound which either three organic radicals each bonded via a carbon atom or two such Contains radicals and a hydrogen atom, from a non-identical aluminum compound of the general formula A1R'R "R" ', in which R' is an alkyl radical, R "is an alkyl or Alkoxy radical or a halogen atom and R "'denotes an alkoxy radical or a halogen atom, and from a titanium compound of the general formula Ti (R "') 4, in which R"' is the same The meaning is as in the preceding formula, available catalyst system used. - Publications considered: Belgian patent specification no. 551 180; Angew. Chem., Vol. 69, 1957, pp. 397, 398.