CN101143919A - A kind of method that catalyzes unsaturated cycloaliphatic compound to synthesize cycloaliphatic epoxy resin - Google Patents

Abstract

A method for catalyzing unsaturated alicyclic compounds to synthesize alicyclic epoxy resins, using a metal compound with oxidation as a catalyst (I), using hydrogen peroxide or alkyl hydroperoxide as an oxygen source, in an organic solvent , unsaturated alicyclic compounds selectively catalyze epoxidation to synthesize alicyclic epoxy resins; the reaction temperature is from 0 to 90 ° C; the reaction lasts for more than 20 minutes; wherein C=C in unsaturated alicyclic compounds and peroxidation The molar ratio of hydrogen or alkyl hydroperoxide is 0.01-20:1; the catalyst (I) is 0.05-10% of the molar amount of the unsaturated alicyclic compound. The invention has a simple reaction system, high selectivity to alicyclic epoxy resins, environmental friendliness, low production cost, can meet technical and economic requirements, and is a new approach suitable for large-scale industrial production of alicyclic epoxy resins.

Description

A kind of method that catalyzes unsaturated cycloaliphatic compound to synthesize cycloaliphatic epoxy resin

technical field

The invention relates to the synthesis of cycloaliphatic epoxy resin, in particular to a method for catalyzing the epoxidation of unsaturated cycloaliphatic compounds to synthesize cycloaliphatic epoxy resin.

Background technique

Alicyclic epoxy resins are usually a class of epoxy compounds obtained by oxidizing corresponding unsaturated alicyclic compounds with peroxidic organic acids. Its structural feature is that it contains an alicyclic ring, and the epoxy group is directly connected to the alicyclic ring. This type of resin has excellent electrical properties such as arc resistance, high volume resistance and surface resistance, and is suitable for use as electrical insulation materials in high-voltage environments. At the same time, this kind of resin has high cross-linking degree, good heat resistance, strong weather resistance, UV resistance and electronic radiation resistance, so it is suitable for outdoor use. It can be used as high temperature resistant adhesive and UV resistant coating for long-term outdoor use. For example, cycloaliphatic epoxy resin ERL-4221 is synthesized by United Carbon Chemical Company [US 2,716,123] using peracid method. There are other cycloaliphatic epoxy resins as follows:

Contents of the invention

The object of the present invention is to provide a kind of method that catalyzes unsaturated cycloaliphatic compound to synthesize cycloaliphatic epoxy resin, and this method reaction system is simple, and post-reaction treatment is easy, and product is single epoxy compound, and production cost is low, safe and non-toxic. Hidden dangers, more friendly to the environment.

In order to achieve the above object, the technical solution adopted by the present invention is:

A method for catalyzing unsaturated cycloaliphatic compounds to synthesize cycloaliphatic epoxy resins,

With the metal compound having oxidation function as the catalyst (I), with hydrogen peroxide or alkyl peroxide as the oxygen source, in an organic solvent, the unsaturated alicyclic compound is selectively catalyzed by epoxidation to synthesize the alicyclic ring Oxygen resin; the reaction temperature is 0 to 100 ° C; the reaction is more than 20 minutes;

Wherein the molar ratio of C=C in the unsaturated alicyclic compound to hydrogen peroxide or alkyl peroxide is 0.01-20: 1; the catalyst (I) is 0.05-10% of the molar dosage of the unsaturated alicyclic compound ;

Catalyst (I) is a heteropolyacid compound Q _m H _n XM _p O _4+3p , M is a central metal atom, which can be Mo, W or V; Q is a cationic part, which can be [R ₁ R ₂ R ₃ R ₄ N ⁺ ], where R ₁ , R ₂ , R ₃ , and R ₄ can be H-, C ₁ -C ₂₀ straight or branched chain alkyl, cycloalkyl, benzyl, or R ₁ R ₂ R ₃ N is pyridine and its homologues; X is a heteroatom, which can be P or As; 2≤m≤7, n=0 or 1; p=2, 3 or 4.

The oxidation reaction catalyst it adopts has been disclosed in the Chinese patent [00123339.4]. It fully exhibits the characteristics of a homogeneous catalyst in the reaction process, has high catalytic activity, and the conversion rate of unsaturated alicyclic compounds is greater than 85%. The selectivity of the reaction is greater than 90%.

This type of catalyst itself is insoluble in the reaction medium, but under the action of hydrogen peroxide, it can form active species soluble in the reaction medium, and then interact with unsaturated alicyclic compounds to selectively catalyze cyclo Oxidation reaction: the conversion rate of unsaturated alicyclic compounds is greater than 95%, the selectivity of the corresponding epoxy compounds to unsaturated alicyclic compounds is greater than 90%, and the catalyst fully reflects the characteristics of a homogeneous catalyst during the reaction process.

The hydrogen peroxide (H ₂ O ₂ ) can be hydrogen peroxide generated in situ or hydrogen peroxide with a weight concentration of 5-90% directly input; the alkyl peroxide (ROOH) is tert-butyl peroxide hydrogen peroxide, ethylbenzene hydroperoxide, cumene hydroperoxide or cyclohexane hydroperoxide in water.

The hydrogen peroxide generated in situ refers to the hydrogen peroxide generated in situ through an oxidation reaction, using the oxygen acceptor _H2A with reversible oxidation and reduction properties as a reducing agent, under the condition of the presence of a reaction medium, in the air Hydrogen peroxide is generated in situ under the action, and the product A oxidized by the reducing agent can be restored to the original structure through catalytic hydrogenation of the catalyst (II), and can be recycled;

The recyclable reducing agent used in the epoxidation reaction is an oxygen-containing or nitrogen-containing compound, wherein A is quinones including benzoquinones, naphthoquinones or anthraquinones, phenazines or azo compounds;

The catalyst (II) used is a transition metal compound containing Ni, Pt, Pd, Cr, Rh, Ru;

The reaction medium is an alkane solvent straight-chain alkane, branched alkane or cycloalkane; an aromatic solvent benzene, toluene, ethylbenzene or alkylbenzene with substituents; a halogenated hydrocarbon solvent halogenated alkane or halogenated arene; Ester solvent fatty acid ester, aromatic ester or trialkyl phosphate; alcohol solvent methanol, ethanol or tert-butanol; the reaction medium used can be a single solvent or a solvent composed of the above solvents.

The oxygen source used in the present invention, the oxygen source can be completely consumed by the epoxidation reaction; if there is an excess oxygen source after the epoxidation reaction, the excess oxygen source can reduce the oxygen by increasing the system temperature or adding a reducing solution. All sources are consumed.

The excess oxygen source is consumed by raising the temperature of the system, and the temperature is between 60-100°C. The preferred temperature is between 70-90°C; the reducing solution is Na ₂ SO ₃ , Na ₂ S ₂ O ₃ or NaHSO ₃ aqueous solution.

The unsaturated alicyclic compound is 3,4-epoxycyclohexanecarboxylic acid-3,4-epoxycyclohexyl ester, 3,4-epoxy-6-methylcyclohexylcarboxylic acid-3,4 - Epoxy-6-methylcyclohexyl ester, dimethylvinyldioxidecyclohexene, vinylcyclohexene dioxide or dicyclopentadiene dioxide. In the epoxidation reaction, the reaction conditions are mild, and the reaction temperature is between 0 and 100°C. The preferred reaction temperature is between 30 and 80°C.

The epoxidation reaction process of the invention is simple and easy, and can prepare alicyclic epoxy resin with high efficiency and high selectivity. What is consumed in the whole process is only unsaturated alicyclic compound, hydrogen peroxide or air, hydrogen and a small amount of catalyst. The reaction system is simple, the production cost is low, the product is a single epoxy compound, there is no co-product, and the post-treatment is simple. The environment is relatively friendly and can meet the requirements of technical economy, and it is a new way suitable for large-scale industrial production of cycloaliphatic epoxy resin.

Detailed ways

Below by example the present invention is given further description.

The following reaction catalyst has been disclosed in Chinese patent [00123339.4], and its preparation process is carried out with reference to CN00123339.4;

Dicyclopentadiene diepoxide is produced by epoxidation of dicyclopentadiene, and it is a white solid. The material made of it has good heat resistance, high hardness, good weather resistance and electrical insulation properties, and can be used It is used in casting adhesives for high temperature transformers and micro motors, adhesives for structural parts, adhesives for glass fiber reinforced plastics and laminated plastics, etc. Domestically, due to technological limitations, only small batches can be produced, and the price is expensive. With the development of petrochemical industry, dicyclopentadiene can be separated from the C5 fraction of petroleum cracking products, and my country has abundant petroleum reserves, which have great development conditions.

The reaction formula is as follows:

The epoxidation of embodiment 1 dicyclopentadiene

Dissolve 40mmol of dicyclopentadiene in 40mL of mesitylene, add 90mmol of 27.5% aqueous hydrogen peroxide (w/w), 0.2mmol of catalyst [(C ₂ H ₅ ) ₃ NCH ₂ Ph] ₂ HA _s Mo ₂ O ₁₀ . After reacting for 1 hour at 65°C, the conversion rate of dicyclopentadiene was 98.3%, and the selectivity of dicyclopentadiene dioxide was 96.3%. After the reaction, Na ₂ S ₂ O ₃ aqueous solution was added to remove excess hydrogen peroxide, and the solvent in the organic layer was evaporated to obtain dicyclopentadiene dioxide crystals. The obtained distilled solvent is then added with oxidation catalyst, dicyclopentadiene and hydrogen peroxide, and the same circulation reaction as above.

它是由中间体The cycloaliphatic diepoxy compound ERL-4221 is a product developed by Union Carbide Corporation of the United States. It is a special-purpose epoxy resin with a molecular formula of

It is made of intermediate

(3-环己烯甲基，3-环己烯甲酸酯)经环氧化制得。而

通常是用

(3-环己烯甲醛)在溶剂和催化剂烷基铝存在下经梯森科(Tischenko)反应制得。

(3-cyclohexene methyl, 3-cyclohexene carboxylate) obtained by epoxidation. and

usually used

(3-Cyclohexene formaldehyde) in the presence of a solvent and a catalyst alkylaluminum by Tischenko (Tischenko) reaction in the system.

At present, there is no industrial production device for the production of cycloaliphatic diepoxide ERL-4221 in China. United Carbon Chemical Company [US 2,716,123] adopts the peracid method. Due to the potential safety hazards of the peracid method, the industrial process is difficult to control. In addition, the chlorohydrin method is used to synthesize epoxy compounds. The chlorohydrin method itself has many problems to be solved, such as serious equipment corrosion, complicated production process, and serious environmental pollution.

The reaction formula is as follows:

R=H, alkyl

The epoxidation of embodiment 2 unsaturated cyclohexene compound A (3-cyclohexene methyl group, 3-cyclohexene carboxylate)

80mmol of material A was dissolved in 40mL mesitylene, 180mmol of 30% hydrogen peroxide aqueous solution (w/w) and 0.4mmol of catalyst [(C ₂ H ₅ ) ₃ NCH ₂ Ph] ₂ HAsMo ₂ O ₁₀ were added. At 65°C, after reacting for 1 hour, the conversion rate of raw material A was 90.0%, and the selectivity of epoxy products was 95.7%. _{Aqueous Na2S2O3 was} added. Remove excess hydrogen peroxide, and distill off unreacted raw material polyene compound A and epoxy products in the organic layer.

The epoxidation of embodiment 3 unsaturated cyclohexene compound A (3-cyclohexene methyl group, 3-cyclohexene carboxylate)

Dissolve 2-menaquinone 40mmol in a mixed solvent of 30mL dimethyl phthalate and 30mL diisobutylmethanol, add 4% of 5% Pd-C (W/W) catalyst, 6atm hydrogen, 45 °C for 6 hours to hydrogenate 2-menaphthoquinone up to 50%. The hydrogenation was stopped, and the Pd-C catalyst was removed by filtration. Then add raw material polyene compound A2mmol in the filtrate, catalyst (NH ₄ ) ₂ HAsW ₂ O ₁₀ 0.09mmol, under 1atm O ₂ , 65 ℃ of reaction 2 hours, the transformation rate of raw material A is 91.0%, the selection of epoxy product The sex is 93.5%. Unreacted starting material A and epoxy product were distilled off.

The epoxidation of embodiment 4 unsaturated alicyclic compound A (3-cyclohexene methyl group, 3-cyclohexene carboxylate)

Dissolve 0.2 mol of raw material A in 100 mL of chloroform, add 0.8 mmol of catalyst [μ-C ₅ H ₅ NC ₁₂ H ₂₅ ] ₃ PW ₄ O ₁₆ , add dropwise 0.5 mol of 30% aqueous hydrogen peroxide (w/w), At 60°C, after reacting for 3 hours, the conversion rate of raw material A was 95.0%, and the selectivity of epoxy products was 95.7%. _{Aqueous Na2S2O3 was} added. Remove excess hydrogen peroxide, and distill off unreacted raw material polyene compound A and epoxy products in the organic layer.

Above-mentioned example shows, adopts the oxidation reaction catalyst that provides in the patent of invention [00123339.4], in suitable reaction medium, according to the condition that the present invention provides, raw material unsaturated cycloaliphatic compound can be efficiently, highly selectively Catalyzed epoxidation to cycloaliphatic epoxy resins. The oxygen source can be directly input hydrogen peroxide (H ₂ O ₂ ); it can also be generated in situ by an oxidation reaction, using the oxygen acceptor H ₂ A with reversible oxidation and reduction properties as the reducing agent, under the action of air Hydrogen peroxide is generated in situ, and the product A oxidized by the reducing agent is restored by simple catalytic hydrogenation and can be recycled. During the reaction process, the catalyst dissolves in the reaction system, which fully reflects the characteristics and functions of the homogeneous catalyst, so the reaction conditions are mild. In the overall reaction process, only unsaturated alicyclic compounds, hydrogen peroxide or air, hydrogen and a small amount of catalyst are consumed, the production cost is low, the product is a single epoxy compound, there is no co-product, and it is more friendly to the environment. The reaction process is simple and easy, can meet the technical and economic requirements, and is a new way suitable for large-scale industrial production of epoxy compounds.

Claims (9)

1. the method for a synthesizing alicyclic epoxy resin by catalyzing unsaturated alicyclic compound is characterized in that:

With the metallic compound with oxygenizement is catalyzer (I), is oxygen source with hydrogen peroxide or alkyl peroxide, in organic solvent, and unsaturated cycloaliphatic compound selective ground catalysis epoxidation synthesis of alicyclic epoxy resin; Temperature of reaction is at 0 to 90 ℃; Reaction is more than 20 minutes;

Wherein the mol ratio of the C=C in the unsaturated cycloaliphatic compound and hydrogen peroxide or alkyl peroxide is 0.01-20: 1; Catalyzer (I) is the 1-15wt% of unsaturated cycloaliphatic compound amount;

Catalyzer (I) is the heteropllyacids compound Q _mH _nXM _pO _4+3p, M is a central metal atom, can be Mo, W or V; Q is a cationic moiety, can use [R ₁R ₂R ₃R ₄N ⁺] expression, wherein R ₁, R ₂, R ₃, R ₄Can be H-, C ₁-C ₂₀The alkyl of straight or branched, cycloalkyl, benzyl, or R ₁R ₂R ₃N is pyridine and homologue thereof; X is a heteroatoms, can be P or As; 2≤m≤7, n=0 or 1; P=2,3 or 4.

2. according to the described method of claim 1, it is characterized in that:

Described hydrogen peroxide (H ₂O ₂) can be the hydrogen peroxide of generated in-situ hydrogen peroxide or weight concentration 2-90%; Described alkyl peroxide (ROOH) is tertbutyl peroxide, ethylbenzene hydroperoxide, isopropyl benzene hydroperoxide or cyclohexane superoxol.

3. according to the described method of claim 2, it is characterized in that:

Described generated in-situ hydrogen peroxide is meant the hydrogen peroxide that produces by the oxidizing reaction original position, utilizes the oxygen acceptor H with reversible oxidation, reducing property ₂A is a reductive agent, under the condition that reaction medium exists, and in-situ hydrogen peroxide under air effect, the product A after the reductive agent oxidation can reset into original texture through catalyzer (II) shortening, and recirculation is used;

The used reductive agent that can be recycled is to contain oxygen or nitrogenous compound in the epoxidation reaction, and wherein A is benzoquinones class in the quinones, naphthoquinones class or anthraquinone class, azophenlyene class or azo compound.

4. according to the described method of claim 3, it is characterized in that: used catalyzer (II) is to contain Ni, Pt, Pd, Cr, Rh and/or Ru transistion metal compound.

5. according to the described method of claim 3, it is characterized in that:

Described reaction medium is alkane solvents straight-chain paraffin, branched paraffin or naphthenic hydrocarbon; Aromatic hydrocarbon solvent benzene, toluene, ethylbenzene or dimethylbenzene; Halogenated hydrocarbon solvent halogenated alkane or halogenated aryl hydrocarbon; Esters solvent fatty acid ester, aromatic esters or trialkylphosphate; Alcoholic solvent methyl alcohol, ethanol or the trimethyl carbinol; Employed reaction medium can be above-mentioned single solvent, also can be the mixed solvent of above-mentioned more than one solvent compositions.

6. according to the described method of claim 1, it is characterized in that: oxygen source used in the present invention, oxygen source can all consume by epoxidation reaction; If there is superfluous oxygen source after the epoxidation reaction, unnecessary oxygen source can all consume oxygen source by the solution that rising system temperature or adding have a reductibility.

7. according to the described method of claim 6, it is characterized in that: described by the rising system temperature to consume superfluous oxygen source, temperature is between 60-100 ℃.

8. according to the described method of claim 6, it is characterized in that: the solution of described reductibility is Na ₂SO ₃, Na ₂S ₂O ₃Or NaHSO ₃The aqueous solution.

9. according to the described method of claim 1, it is characterized in that: described unsaturated cycloaliphatic compound is a 7-oxabicyclo [4,1,0] heptane-3-carboxylic acid, 7-oxabicyclo [4,1,0] heptan-3-methyl ester, 3,4-epoxy group(ing)-6-methyl cyclohexane formic acid-3 ', 4 '-epoxy group(ing)-6 '-methyl cyclohexane ester, dimethyl are for vinyl cyclohexene dioxide, vinyl cyclohexene dioxide or bicyclopentadiene dioxide.