CN100457268C - Catalyst of acetylacetone metal supported and carried by ion liquid, and preparation method - Google Patents

Abstract

An ionic liquid carried acetylacetone-metal catalyst able to be easily recovered from reaction system by water washing is prepare through reaction between substituted acetylacetone and imidazole at -20-150 deg.C to obtain ionic liquid carried acetylacetone, and the complex reaction between said ionic liquid carried acetylacetone and transition metal at 0-100 deg.C.

Description

Catalyst and preparation method of metal acetylacetonate supported by ionic liquid

technical field

The invention relates to a catalyst and a preparation method of a metal acetylacetonate supported by an ionic liquid.

Background technique

As everyone knows, acetylacetone metal reagent is an excellent reaction process in oxidation reaction (US4970347, US4046813, CN1425642), ring-opening polymerization reaction, graft polymerization reaction (CN1470534, CN1405192, CN1405192, CN1422876, CN1263520, CN1470535, CN1572809) etc. catalyst. However, the use of acetylacetonate metal catalysts in these reactions also has its inherent disadvantages. Taking oxidation reactions as an example (US4970347, US4046813), because acetylacetone metal catalysts have good solubility in the organic phase, they can be well dissolved Due to the reaction system, it brings difficulties to the aftertreatment process and the recovery of the catalyst: by the method of water washing and extraction, it is difficult to recover it due to the poor solubility of metal acetylacetone catalysts in water; by the method of rectification, due to The by-products (especially some polymerization by-products) produced during the reaction often remain in the scrap during rectification. This part of the by-products is mixed with the metal acetylacetonate catalyst, and the metal acetylacetonate catalyst should be extracted from it It is also quite difficult, and the metal acetylacetone catalyst is also easily destroyed in the high-temperature rectification process.

Contents of the invention

The object of the present invention is to provide a catalyst and a preparation method of metal acetylacetonate supported by a class of ionic liquid. This catalyst can be simply recovered from the reaction system by washing with water after the reaction.

The abbreviated formula of the acetylacetone metal catalyst supported by the ionic liquid involved in the present invention is: [ace-Cnmim][X]-M, wherein ace represents the type of acetylacetone, mim represents the type of imidazole, X represents the type of anion, and M represents Metal ions have the general formula:

Where n=1~6; M1 is trivalent transition metal Fe ³⁺ , Cr ³⁺ , V ³⁺ , M2 is bivalent transition metal Ti ²⁺ , Mn ²⁺ , Fe ²⁺ , Co ²⁺ , Ni ²⁺ , Cu ²⁺ ; R1, R2, R3 are H, straight-chain or branched-chain hydrocarbons with the general formula C _m H _2m+1 (m=1~6) or C _m H _2m (m=1~6), Phenyl or substituted phenyl; X is BF ₄ ^- , PF ₆ ^- , SbF ₆ ^- , H ₂ PO ₄ ^- , F ^- , Cl ^- , Br ^- , HSO ₄ ^- , NO ₃ ^- anion.

The metal acetylacetonate catalyst supported by the ionic liquid involved in the present invention can specifically be prepared by the following two-step reaction: 1) react the acetylacetonate supported by the ionic liquid with an imidazole in a suitable organic solvent to obtain the acetylacetonate supported by the ionic liquid Acetone, the reaction formula is as follows:

2) The acetylacetone supported by the ionic liquid reacts with the transition metal salt in a suitable organic solvent to form a complexed acetylacetone metal catalyst supported by the ionic liquid.

The organic solvent used in the reaction of the present invention may be one or more of acetone, methyl ethyl ketone, pentanone, tetrahydrofuran, ether, isopropyl ether, and monohydric alcohols with 1 to 6 carbon chains.

The temperature suitable for the first step reaction of the present invention is between -20°C and 150°C, and preferably between 0°C and 100°C; the temperature suitable for the second step reaction is between -20°C and 100°C, and preferably between Between 0°C and 80°C.

In the first step reaction, the molar ratio of substituted acetylacetones and imidazoles is between 0.1～10, and preferably between 0.5～5; in the second step reaction, the acetylacetone supported by ionic liquid and The molar ratio of the transition metal salt is between 0.1-10, and preferably between 1-5.

The present invention is different from previous inventions in that: the metal acetylacetonate catalyst prepared by the method has good solubility in water while being soluble in conventional organic solvents, and the solubility in water is often greater than the solubility in organic solvents . Thereby making the acetylacetonate metal catalyst supported by the ionic liquid in the reaction process can be well dissolved in the reaction system, and the catalyst can be removed from the reaction system by simple water washing after the reaction, and then evaporated under reduced pressure In addition to moisture, to achieve the purpose of catalyst recovery.

The following examples will more fully describe the present invention.

Detailed ways

Example 1

Add 16.4g (0.2mol) of methylimidazole and 150ml of acetone into a 250ml three-necked flask, stir and cool down to 0°C, slowly add 33.5g (0.25mol) of chloroacetylacetone dropwise within 2 hours, and then raise the temperature Stirring was continued to room temperature for 8 hours. Distill under reduced pressure to constant weight to obtain 39.3 g of chloromethylimidazole acetylacetone (yield: 91.0%).

Example 2

In a 250ml three-necked flask, add 10.8g (0.04mol) ferric chloride hexahydrate and 100ml ethanol, in a constant pressure dropping funnel of 100ml, 26.0g (0.12mol) chloromethylimidazole acetylene obtained in Example 1 Dissolve acetone in 80ml of ethanol, raise the temperature to 40°C with stirring, slowly add the ethanol solution of chloromethylimidazole acetylacetone dropwise within 2 hours, and continue to keep warm and stir for 5 hours after the drop is completed. Distill under reduced pressure to constant weight to obtain 27.9 g of chloromethylimidazolium acetylacetonate iron (III) (yield: 99.2%).

Example 3

Add 16.4g (0.2mol) of methylimidazole and 150ml of methanol into a 500ml three-necked flask, stir and cool down to 0°C, slowly add 33.5g (0.25mol) of chloroacetylacetone dropwise within 2 hours, and then raise the temperature Stirring was continued to room temperature for 8 hours.

In the constant pressure dropping funnel of 250ml, add the mixed solution of 18.1g (0.067mol) iron trichloride hexahydrate and 150ml methanol. The solution in the three-necked flask was heated up to 40°C with stirring, and the methanol solution of ferric chloride was slowly added dropwise within 2 hours, and continued to keep stirring for 5 hours after the drop was completed. Distill under reduced pressure to constant weight to obtain 46.2 g of chloromethylimidazolium acetylacetonate iron (III) (yield: 98.1%).

Example 4-14

Similar to Example 3, different substituted acetylacetone substances, imidazole substances, organic solvents, and transition metal salts were used respectively, and the following results were obtained after the reaction:

Example Substituted acetylacetone (mol) Imidazole (mol) Organic solvent (ml) Transition metal salt (mol) Catalyst yield 4 Chloroacetylacetone 0.20 Imidazole 0.22 Methanol 300 FeCl₃ 0.067 92.3% 5 Bromoacetylacetone 0.20 Methylimidazole 0.25 Methanol 300 FeCl₃ 0.067 93.8% 6 Bromoacetylacetone 0.20 Imidazole 0.22 Methanol 300 FeCl₃ 0.067 90.1% 7 Chloroacetylacetone 0.20 Butylimidazole 0.25 Acetone 400 CuCl₂ 0.10 98.7% 8 Chloroacetylacetone 0.20 Imidazole 0.22 Acetone 400 CuCl₂ 0.10 94.9%

9 Bromoacetylacetone 0.20 Butylimidazole 0.25 Acetone 400 CuCl₂ 0.10 95.3% 10 Bromoacetylacetone 0.20 Methylimidazole 0.25 Acetone 400 CuCl₂ 0.10 91.2% 11 3-Chloroethyl-acetylacetone 0.20 Methylimidazole 0.25 Methanol 300 FeCl₃ 0.067 95.8% 12 3-Bromopropyl-acetylacetone 0.20 Butylimidazole 0.25 Acetone 400 CuCl₂ 0.10 93.5% 13 3-Chloroethyl-acetylacetone 0.20 Imidazole 0.22 Acetone 400 CuCl₂ 0.10 92.1% 14 3-Bromopropyl-acetylacetone 0.20 Methylimidazole 0.25 Methanol 300 FeCl₃ 0.067 90.0%

Claims (5)

1, a kind of ion liquid supported cetylacetone metallic catalyst, structural formula is as follows:

N=1～6 wherein; M1 is the trivalent transition-metal Fe ³⁺, Cr ³⁺, V ³⁺M2 is divalent transition metal Ti ²⁺, Mn ²⁺, Fe ²⁺, Co ²⁺, Ni ²⁺, Cu ²⁺R ₁, R ₂, R ₃Independently be H or have general formula C respectively _mH _2m+1Straight-chain hydrocarbons or branched-chain hydrocarbons, m=1 in the formula～6; X ^-Be F ^-, Cl ^-, Br ^-Anion.

2, the described ion liquid supported cetylacetone metallic Preparation of catalysts method of claim 1 the steps include:

1) will replace levulinic ketone material and imidazoles material, the mixed in molar ratio by 0.1～10 in appropriate organic solvent, is reacted under-20 ℃～150 ℃ temperature, gets ion liquid supported acetylacetone,2,4-pentanedione, and reaction equation is as follows:

N=1～6 wherein; R ₁, R ₂, R ₃Independently be H or have general formula C respectively _mH _2m+1Straight-chain hydrocarbons or branched-chain hydrocarbons, m=1 in the formula～6; X is F, Cl, Br; X ^-Be F ^-, Cl ^-, Br ^-Anion;

2) with above-mentioned ion liquid supported acetylacetone,2,4-pentanedione and transition metal salt, the mol ratio by 0.5～5 in appropriate organic solvent, is reacted under 0 ℃～100 ℃ temperature, and complexing generates ion liquid supported cetylacetone metallic catalyst.

3, method according to claim 2 is characterized in that replacing levulinic ketone material and imidazoles material mol ratio is 0.5～5, and the ion liquid supported acetylacetone,2,4-pentanedione and the mol ratio of transition metal salt are 1～5.

4, method according to claim 2, the reaction temperature that it is characterized in that obtaining ion liquid supported acetylacetone,2,4-pentanedione is 0 ℃～100 ℃, it is 0 ℃～80 ℃ that complexing generates ion liquid supported cetylacetone metallic catalyst reaction temperatures.

5, method according to claim 2 is characterized in that appropriate organic solvent is more than one in the monohydric alcohol of acetone, butanone, pentanone, oxolane, ether, isopropyl ether, 1～6 carbochain.