KR100336114B1 - Isomerization of isolated double bonds in cyclioolefin - Google Patents

Abstract

The present invention relates to an isomerization method of a cycloolefin having a non-conjugated double bond, wherein the molecular formula L _4-n MX _n (M is titanium, zirconium or hafnium, X is halogen, and L is 3 to 8 π electron donor ligands). And n is 1, 2 or 3.) and a Group 4 metal compound represented by the general formula R _m AlX _3-m (R is a C ₁ to C ₂₀ alkyl group or an aryl group, m is 1, 2 or 3). X is a halogen or a C _{1 to} C ₁₀ alkyl group, an alkoxy group, or when m = 2, X is a halogen or hydrogen. By shifting the bonds, high activity and selectivity are given to the isomerization of cycloolefins having nonconjugated double bonds, and the yield is improved.

Description

Isomerization method of cycloolefin having nonconjugated double bond {ISOMERIZATION OF ISOLATED DOUBLE BONDS IN CYCLIOOLEFIN}

The present invention relates to a method for isomerization by the catalyst of cycloolefin having a non-conjugated double bond.

In general, cycloolefins having nonconjugated double bonds are used as intermediates or monomers of polymer reactions, and also by reactions using double bonds such as epoxidation, addition, and Diels-Alder reactions. Provides compounds useful in petrochemicals and fine chemistry.

Therefore, as the cycloolefin having a structure in which the double bond is disposed in an appropriate position is required according to the nature of the chemical reaction and the final synthetic purpose, many studies have been conducted for a long time about the isomerization reaction of the cycloolefin by the transfer reaction of the double bond. The main task is to develop a catalyst that provides high yield and selectivity without damaging the double bonds due to polymer polymerization.

4-vinylcyclohexene (4-VCH) and 1,5-cyclooctadiene (1,5-COD) in cycloolefins having nonconjugated double bonds Obtained as a dimer, the catalyst system which causes the double bond transfer reaction of these compounds can be divided into two types.

The first is the isomerization of olefins with base, using 4-base catalyst of potassium tert -butoxide in dimethyl sulfoxide solvent as shown in Schemes 1 and 2 Isomerization of VCH and 1,5-COD to 3-ethylidenecyclohexene (3-ECH) and 1,3-COD, respectively, occurs in S. Bank. J. Org. Chem ., Vol. 33. 1968. p. 221 and D. Devaprabhakara. J. Am. Chem. Soc. , vol. 85. 1963. p. 1553. At this time, 1,5-COD was quantitatively converted to 1,3-COD, but in the case of 4-VCH, conversion to 3-ECH was low and other by-products were produced together.

In addition, U. S. Patent No. 3,340, 317 describes a method for converting 4-VCH to 3-ECH in 67% yield by reacting at 140 DEG C for 7 hours using magnesium oxide, and U.S. Patent No. 4,434,310 for hydrogenation. A method of converting 1,5-COD to 1,3-COD by reaction at 150 ° C. for 5 hours using a sodium / amine compound catalyst system is described.

On the other hand, U.S. Patent No. 3,523,979 discloses 1,5-COD as 2-bicyclo [3.3.0] octene by the intramolecular cyclization reaction when strong acid is used. A method of switching to is described.

The second is to use metal compounds as catalysts. In the isomerization of 4-VCH, the mixture was refluxed using a hexacarbonyl metal compound, an organic acid, and triphenylphosphin, and the reaction mixture of 3-ECH and 4-ECH was 80% or more after 3 to 24 hours. Obtained in U.S. Patent No. 3,363,014, and U.S. Patent No. 3,390,193 discloses 8 at 150 ° C when using acetylacetonatonickel, alkylaluminum and isobutylene. It is shown that 80% of the mixture of 3-ECH and 4-ECH is obtained in the product which was distilled under reduced pressure after reaction for some time.

On the other hand, as for the isomerization of 1,5-COD, since 1,5-COD forms complexes with various metals well, many studies on the isomerization reaction using a metal compound catalyst have been reported. Here are a few of the typical ones.

First of all, JEArnet. J. Am. Chem. Soc. , vol. 83. 1961. Using pentacarbonyl iron [Fe (CO) ₅ ] of p. 2954 as a catalyst and reacting at 115 ° C. for 7 hours and dichlorobis (benzonitrile) palladium [PdCl ₂ · 2 (US Patent No. 3,387,045). C ₆ H ₅ CN)] and reacted for 1 hour while refluxing with a tetrabutoxylated titanium [Ti (OBu) ₄ ] / alkyl aluminum catalyst system of US Pat. No. 4,513,157 and reacted for 1 hour. As a result, most of 1,3-COD can be obtained more than 90%.

In addition, in the isomerization reaction using a metallocene catalyst, the reaction was performed for 2 to 5 hours at 180 ° C. using a dichlorobis (cyclopentadienyl) titanium / lithium aluminum hydride (LiAlH ₄ ) catalyst system. Isomerization of diene (linear 1,5-diene) compounds and vinylcycloalkanes occurs in K.Mach. Synthrsis , 1962. p.53.

Similar reactions occurred in the case of using a dichlorobis (cyclopentadienyl) titanium / brominated isopropylmagnesium ( i C ₃ H ₇ MgBr) catalyst system. Qian Yanlong J. Mol. Catal. , vol. 34. 1986. p.31 shows that when the molar ratio of 1,5-COD to titanium in the catalyst system is 1: 200, 1,5-COD is quantitatively converted to 1,3-COD under 25 ° C for 1 hour. Is shown.

In addition, when the catalyst system was used for 4-VCH, as in Scheme 4, 88% of 4-ECH was obtained as a result of reacting for 2 hours at 15 ° C. at a low temperature with a molar ratio of 4-VCH to titanium of 20. When reacted at 50 ° C. for 2 hours, 99% of 3-ECH was obtained from Lu Jiaqui. Acta Chemica Sinica , vol. 46. 1989. p.711.

In the prior art, 4-ECH is obtained when only a vinyl group having a higher double bond activity than a ring double bond is reacted in 4-VCH isomerization reaction, and 3-ECH when two double bonds are moved. It is shown that ECH is obtained. By the way, in several catalytic reactions of 4-VCH, the yield was lowered at low temperature, and the yield was improved at high temperature, but the selectivity was generally lowered, resulting in a mixture of 3-ECH and 4-ECH. In addition, since 3-ECH and 4-ECH, which may be called isomers, are not easily separated, it is preferable to generate them by a selective catalyst.

In addition, since the metallocene catalyst is sensitive to temperature, when the metallocene catalyst is reacted at a high temperature, the stability thereof is lowered, so that an excessive amount of catalyst is inevitable.

The present invention has been made to solve the above problems, and an object thereof is to provide a method for isomerizing a cycloolefin having a nonconjugated double bond by a catalyst having high activity and selectivity.

The present invention for achieving the above object is an unsaturated having a non-conjugated double bond by using a Group 4 metal compound represented by the molecular formula L _4-n MX _n and an organoaluminum compound represented by the general formula R _m AlX _3-m as a catalyst It is characterized by moving the double bond of the cycloolefin.

Hereinafter, a method for isomerizing a cycloolefin having a nonconjugated double bond according to the present invention will be described.

The cycloolefin applied to the present invention is an unsaturated cycloolefin having a non-conjugated double bond, a ring composed of 6 or more and 12 or less carbons, and optionally having a substituent introduced. Such olefins include 4-vinylcyclohexene, dipentene, 4-isopropenylcyclohexene and their alkyl group substituents, 1,5-cyclooctadiene and 1,4-cyclooctadiene and their respective alkyl group substituents, 1,5,9-cyclododecatriene and the like.

The double bond of the cycloolefin can be moved by a reaction using an isomerization catalyst, and the isomerization reaction in the present invention is carried out in the presence of a catalyst system composed of a Group 4 metal compound and an organoaluminum compound.

The Group 4 metal compound is a metal compound represented by the molecular formula L _4-n MX _n , M is titanium, zirconium or hafnium, X is halogen, L is a ligand of 3 to 8 π electron donors, n is 1 , 2 or 3.

In this case, the ligand L is η ³ - allyl ^{(η 3 -allyl), η 5} - cyclopentadienyl ^{(η 5 -cyclopentadienyl), η 7} - cycloheptane-butadiene days (η ⁷ -cycloheptatrienyl) and derivatives thereof and η ⁶ - is an aromatic (η ⁶ -aromatics) - benzene (η ⁶ -benzene) and η ⁶ containing derivatives thereof.

These Group 4 metal compounds include trichlorocyclopentadienyltitanium trichloride, dichlorobis (cyclopentadienyltitanium dichloride), trichloroindentitanium trichloride, and trichloropentatan trichloride. Methylcyclopentadienyl titanium (pentametylcyclopentadienyltitanium trichloride), dichlorobis (cyclopentadienyl) zirconium (biscyclopentadienylzirconium dichloride), dichlorobis (indenyl) zirconium (bisindenylzirconium dichloride), dichlorobis (pentamethyl cyclopenta dipentane) Nyl) titanium (bispentametylcyclooentadienyltitanium dichloride), trichlorocyclopentadienyl zirconium (cyclopentadienylzirconium trichloride), trichloropentamethylcyclopentadienyl zirconium (pentametylcyclopentadienylzirconium trichloride), dichlorobi Biscyclopentadienyl hafnium dichloride and the like.

And the organoaluminum compound is represented by the general formula R _m AlX _3-m , where R is C _{1 ~} C ₂₀ Alkyl group or aryl group, m is 1, 2 or 3, X Is halogen or C ₁ -C ₁₀ alkyl group, alkoxy group or m = 2, X is halogen or hydrogen.

The organoaluminum compound is triethylaluminum, triisobutylaluminum, trihexylaluminum, trioctylaluminum, diethylaluminum chloride, ethoxylated diethylaluminum ( diethylaluminum ethoxide, ethylaluminum sesquichloride, diethylaluminum hydride, diisobutylaluminum hydride, diethylaluminum fluorid, diisobutylaluminum fluoride diisobutylaluminum fluoride).

On the other hand, when isomerizing cycloolefin using such a compound, the mole ratio of the Group 4 metal compound to the cycloolefin is preferably 10 ⁻³ to 10 ⁻¹ , and the Group 4 metal compound. 0.5-25 are suitable and, as for the molar ratio of the organoaluminum compound with respect to, 1-10 are more preferable.

In the method of adding a catalyst to the reaction system in the present invention, the Group 4 metal compound is separately added to the organoaluminum compound, or the Group 4 metal compound and the organoaluminum compound are mixed in a solvent in advance, and then the mixture is added to the reaction system. In the latter case, the catalyst can be easily stored and handled during injection.

On the other hand, in the isomerization of cycloolefin according to the present invention, a solvent may be used, and the reaction solvent used may be an aromatic hydrocarbon, a saturated aliphatic hydrocarbon, or the like, which is not reactive toward the catalyst or the reactant. That is, such reaction solvents include alkyl benzenes such as benzene, toluene, xylene and mesitylene, alkanes such as hexane, cyclohexane, octane and isooctane or cyclo alkanes and diglyme, dioxane ( ethers such as dioxane, tetrahydrofuran and the like.

Reaction temperature for advancing this invention is 50-200 degreeC, and it is more preferable to advance between 80-160 degreeC.

In addition, the reaction of the present invention proceeds in anhydrous atmosphere in the presence of an inert gas such as nitrogen and argon.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the scope of the present invention is not limited to the following Examples.

The isomerization of all the following examples was carried out in anhydrous atmosphere in the presence of nitrogen gas using a vacuum line.

<Example 1>

In a dry box, 0.001 mol (mol) of dichlorobis (cyclopentadienyl) titanium (Cp ₂ TiCl ₂ ) is placed in a flask, and then taken out to be connected to a vacuum line. In anhydrous atmosphere in the presence of nitrogen gas, 0.100 mol of 1,5-COD is added and stirred for about 15 minutes. When triethylaluminum (AlEt ₃ ) is added to this solution, the color of the reaction solution turns blue while Cp ₂ TiCl ₂ is dissolved. After reacting at 100 ° C. for 2 hours, a sample was taken and analyzed by gas chromatography (Gas Chromatography).

Comparative Example 1

The reaction was carried out in the same manner as in Example 1, but without addition of AlEt ₃ , and a sample was taken and analyzed by gas chromatography. Only unreacted 1,5-COD was detected.

<Examples 2-5>

After varying the type and amount of the organoaluminum compound, the reaction was carried out at 100 ° C. under the same conditions as in Example 1, and the samples were taken and analyzed by gas chromatography. The organoaluminum compound used at this time is AlEt ₃ , hydrogenated diisobutylaluminum (DIBAL-H) and trimethylaluminum (AlMe ₃ ).

Example Al catalyst 1,5-COD: Cp ₂ TiCl ₂ : Al (mol) Response time (h) yield(%) 1,5-COD 1,4-COD 1,3-COD 2 AlEt ₃ 100: 1: 5 2.0 31 28 40 3 DIBAL-H 100: 1: 2 2.0 9 12 80 4 DIBAL-H 100: 1: 5 2.0 - trace 100 5 AlMe ₃ 100: 1: 2 4.0 74 21 5

<Examples 6-11>

The type and amount of the Group 4 metal compound were varied, and the reaction was carried out at 100 ° C. under the same conditions as in Example 1, and then the samples were taken and analyzed by gas chromatography. The Group 4 metal compounds used at this time are dichlorobis (cyclopentadienyl) zirconium (Cp ₂ ZrCl ₂ ) and dichlorobis (cyclopentadienyl) hafnium (Cp ₂ HfCl ₂ ). When added, the Group 4 metal compound was dissolved, and the reaction solution turned yellow.

Example Cp ₂ MCl ₂ Al catalyst 1,5-COD: Cp ₂ TiCl ₂ : Al (mol) Hours (h) yield(%) 1,5-COD 1,4-COD 1,3-COD 6 Cp ₂ ZrCl ₂ AlEt ₃ 100: 1: 2 1.0 trace trace 100 7 Cp ₂ ZrCl ₂ DIBAL-H 100: 1: 5 1.0 trace trace 100 8 Cp ₂ ZrCl ₂ DIBAL-H 100: 0.4: 2 2.0 trace trace 100 9 Cp ₂ ZrCl ₂ DIBAL-H 100: 0.2: 1 2.0 3 4 93 10 Cp ₂ HfCl ₂ AlMe ₃ 100: 1: 2 4.0 85 14 2 11 Cp ₂ HfCl ₂ DIBAL-H 100: 1: 5 4.0 16 18 66

<Examples 12-14>

In a dry box, a quantity of Cp ₂ TiCl ₂ is put into a flask and taken out to a vacuum line. After distillation under reduced pressure under a nitrogen atmosphere, 0.100 mol of 4-VCH, which was stored frozen, was added and stirred for about 15 minutes. Addition of AlEt ₃ or DIBAL-H to this solution dissolves Cp ₂ TiCl ₂ and changes the color of the reaction solution to blue. After reacting the reaction solution at 100 DEG C for about 4 hours with stirring, a sample was taken and analyzed by gas chromatography to obtain 4-ECH as a main product, in which only a double bond of 4-VCH vinyl group was transferred. These reaction conditions and product analysis are shown in Table 3.

Example Al catalyst 4-VCH: Ti: Al (mol) Response time (h) yield(%) 4-VCH 4-ECH 3-ECH 12 AlEt ₃ 100: 1: 2 4.0 52 40 3 13 AlEt ₃ 100: 2: 5 4.0 33 47 9 14 DIBAL-H 100: 2: 5 4.5 48 30 9

It can be seen from the results of the above examples that the catalyst of the present invention exhibits high activity and selectivity for the isomerization of olefins.

As described above, the use of the catalyst according to the present invention provides high activity and selectivity to isomerization of cycloolefins having nonconjugated double bonds, thereby preventing damage to the double bonds and improving yield. do.

Claims (8)

Group 4 metal compound represented by the molecular formula L _4-n MX _n (M is titanium, zirconium or hafnium, X is halogen, L is 3 to 8 π electron donor ligands, and n is 1, 2 or 3) And general formula R _m AlX _3-m (R is C ₁ -C ₂₀ alkyl group or aryl group, m is 1, 2 or 3, X is halogen or C ₁ -C ₁₀ alkyl group, alkoxy group or m = 2) In this case, X is an organoaluminum compound represented by halogen or hydrogen) and has a ring composed of 6 or more carbon atoms and 12 or less carbon atoms, and transfers double bonds of unsaturated cycloolefins having non-conjugated double bonds. Isomerization method of cycloolefin which has a non-conjugated double bond to be. The method for isomerizing cycloolefins having non-conjugated double bonds according to claim 1, wherein the molar ratio of the organoaluminum compound to the Group 4 metal compound administered to the cycloolefin is 0.5 to 25. The method of claim 1, wherein the molar ratio of the Group 4 metal compound to the cycloolefin is 10 ^-3 to 10 ^-1 . The isomerization method of cycloolefin having a non-conjugated double bond according to claim 1, wherein the reaction temperature of the isomerization reaction is in the range of 50 to 200 ° C. The method of claim 1, wherein the cycloolefin is selected from 4-vinylcyclohexene, dipentene, 4-isopropenyl cyclohexene, and an alkyl group substituent thereof. The method of claim 1, wherein the cycloolefin is 1,5-cyclo octadiene, 1,4-cyclo octadiene and alkyl group substituents thereof, isomerization method of cycloolefin having a non-conjugated double bond . The method of claim 1, wherein the Group 4 metal compound is trichlorocyclopentadienyl titanium, dichlorobis (cyclopentadienyl) titanium, trichloroindenyl titanium, trichloropentamethylcyclopentadienyl titanium , Dichlorobis (cyclopentadienyl) zirconium, dichlorobis (indenyl) zirconium, dichlorobis (pentamethylcyclopentadienyl) titanium, trichlorocyclopentadienylzirconium, trichloropentamethylcyclo A method for isomerizing a cycloolefin having a non-conjugated double bond, characterized in that it is selected from pentadienyl zirconium and dichlorobis (cyclopentadienyl) hafnium. The method of claim 1, wherein the organoaluminum compound is triethylaluminum, triisobutylaluminum, trihexyl aluminum, trioctyl aluminum, diethylaluminum chloride, ethoxylated diethylaluminum, sesquichloride hydrochloride aluminum, diethylaluminum hydride, A method for isomerizing a cycloolefin having a non-conjugated double bond, characterized in that it is selected from hydrogenated diisobutylaluminum, diethylaluminum fluoride, and diisobutylaluminum fluoride.