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Method for isomerizing cis-olefin into trans-olefin

A technology of cis-olefins and olefins, which is applied in the field of olefin compound synthesis, can solve the problems of harsh reaction conditions, industrial application limitations, waste pollution and other problems, and achieve the reduction of production process cost, complexity reduction and simple operation process Effect

Active Publication Date: 2020-11-24
XIAMEN UNIV
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  • Abstract
  • Description
  • Claims
  • Application Information

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Problems solved by technology

These methods can obtain higher yields, but a large amount of phosphine reagents, metal reagents or aldehydes and other additives need to be added in the reaction process, which limits the purification of the product, and a large amount of waste will also pollute the environment.
[0004] There are also some other methods for synthesizing olefinic compounds in recent years: (1) the catalytic reduction method using ammonia borane as a hydrogen source, although this method has milder reaction conditions and low equipment requirements, ammonia borane is expensive and still The complex of metal and ligand needs to be prepared in advance, which increases the production cost and is not conducive to large-scale industrial application; (2) the catalytic reduction method using acid as the hydrogen source, which has reduced the cost compared with the previous method, However, the use of acid will increase the loss of equipment, require more severe conditions, and the industrial application is limited. At the same time, it is difficult to achieve the selective synthesis of trans olefins by this method.
(3) Catalyzed reduction method with alcohol as hydrogen source, such as reacting olefin with alcohol and methyl heterocyclic compound, although this method can obtain higher trans olefin productive rate, the preparation cost of catalyst is high, and reaction temperature needs to be in Around 140°C, the reaction conditions are harsh, so it is not conducive to industrial applications
[0005] In summary, trans-olefin compounds have high application value in the field of medicine and chemical industry, but most of the existing synthetic methods are costly and require harsh reaction conditions, and the waste generated by post-processing will increase the burden on the environment, making industrial application cause more or less restrictions

Method used

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  • Method for isomerizing cis-olefin into trans-olefin
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  • Method for isomerizing cis-olefin into trans-olefin

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preparation example Construction

[0041] In the present invention, the preparation method of palladium / copper compound catalyst can adopt the following steps:

[0042] a. Dispersing the palladium precursor in acetonitrile in advance, stirring at 10-60° C. to obtain a palladium precursor acetonitrile solution, the palladium precursor mass percentage concentration in the palladium precursor acetonitrile solution is 0.001% to 1%;

[0043] b. Disperse the copper compound in acetonitrile, stir in an inert gas atmosphere, add the palladium precursor acetonitrile solution, stir at 40-70°C for 3-7 hours, centrifuge, wash, and vacuum-dry to obtain a palladium / copper compound catalyst; In the palladium / copper compound catalyst, palladium is atomically dispersed on the surface of the copper compound.

[0044] In the present invention, the palladium precursor can be selected from (Ph 4 P) 2 [Pd 2 (μ-CO) 2 Cl 4 ], at least one of diacetonitrile palladium chloride.

Embodiment 1

[0045] Embodiment 1: the catalytic application of palladium / copper compound catalyst

[0046] 1-1: 0.1% Pd 1 / Cu 2 O catalyst preparation

[0047] Pd(CH 3 EN) 2 Cl 2 Disperse in acetonitrile and stir at 10-60°C for 10 hours to obtain Pd(CH 3 EN) 2 Cl 2 Acetonitrile solution, Pd(CH 3 EN) 2 Cl 2 The mass percentage concentration is 0.5%.

[0048] Take 500mg Cu 2 O was dispersed in 100mL of acetonitrile, after ultrasonic dispersion was uniform, at 50sccm N 2 After stirring for 15 minutes under the atmosphere, according to the Pd and Cu 2 The mass ratio of O was 0.1:100 and Pd(CH 3 EN) 2 Cl 2 Acetonitrile solution, stirred at 40-70°C for 3-7 hours, cooled to room temperature, centrifuged, washed with ethanol for several times, and dried in a vacuum oven to obtain 0.1% Pd 1 / Cu 2 O catalyst.

[0049] 1-2: 0.5%Pd 1 / Cu 2 O catalyst preparation

[0050] Pd(CH 3 EN) 2 Cl 2 Disperse in acetonitrile and stir at 10-60°C for 10 hours to obtain Pd(CH 3 EN) 2 Cl ...

Embodiment 2

[0065] Example 2: 0.1% Pd 1 / Cu 2 Catalytic Isomerization Application of O Catalyst

[0066] Take by weighing the 0.1%Pd prepared in five groups of embodiment 1 1 / Cu 2 O catalyst, each group containing 5 μmol Pd, respectively named test group 6, 7, 8, 9, 10, added to a 50mL high-pressure reaction bottle, and then added 1mmol cis-diphenylethylene, cis-1-methyl- 1-styrene, cis-1-phenyl-1-butene, cis-1-phenyl-1-pentene, cis-3-phenyl-2-propen-1-ol, add 10 mL of ethanol as solvent, After mixing well, at 1 bar H 2 Under the atmosphere and at a temperature of 30° C., samples are taken after reacting for 2 to 10 hours, and analyzed by gas chromatography using an internal standard method to determine the performance of the catalyst for catalyzing the isomerization of cis-olefins into trans-olefins. Table 2 for 0.1% Pd 1 / Cu 2 The O catalyst catalyzes the isomerization of different cis olefins into trans olefins. It can be seen that the catalyst prepared by the method of the pres...

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Abstract

The invention provides a method for isomerizing cis-olefin into trans-olefin. The method comprises the following steps: adding a palladium / copper compound catalyst and cis-olefin into a reaction vessel, adding an organic solvent, performing uniform mixing, and performing reacting in a hydrogen atmosphere to obtain the trans-olefin. In the palladium / copper compound catalyst used in the invention, palladium is dispersed on the surface of the copper compound in an atomic scale, H2 is induced to dissociate in a heterogeneous cracking mode by utilizing a special interface formed between Pd and thecarrier, so that C=C double bonds are turned over, cis-olefin is converted into trans-olefin instead of further hydrogenating the cis-olefin into alkane, and the method has high selectivity on the trans-olefin. Meanwhile, the method is simple in operation process and capable of achieving large-scale preparation, does not need various auxiliaries in the catalytic process, reduces the complexity degree of a reaction system, facilitates separation and purification of products, saves the cost, and has extremely high industrial application value.

Description

Technical field: [0001] The invention relates to the field of olefin compound synthesis, in particular to a method for isomerizing cis olefins into trans olefins. Background technique: [0002] Olefin compounds are very important fine chemicals, which play a pivotal role in the pharmaceutical, pesticide, spice and other industries. As an organic synthesis reagent in the chemical industry, olefins can participate in catalytic hydrogenation reactions, electrophilic addition reactions, free radical addition reactions, polymerization reactions, etc., and can produce fluorescent whitening agents, liquid crystals, and light-emitting diodes; It is a very important drug intermediate in the field. The alkene group is a common pharmacophore, which is used to synthesize drugs with physiological activity, or to form fragments of various functional materials, especially trans-alkenes are the most widely used, such as trans The stilbene compounds of the formula not only have remarkable p...

Claims

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Application Information

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Patent Type & Authority Applications(China)
IPC IPC(8): C07C5/22C07C11/02C07C15/52C07C15/46C07C15/44C07C29/56C07C33/30B01J23/89B01J27/24
CPCC07C5/226C07C29/56B01J23/8926B01J27/24C07B2200/09C07C2523/89C07C2527/24C07C11/02C07C15/52C07C15/46C07C15/44C07C33/30
Inventor 郑南峰李凯佳刘锟隆刘圣杰陈洁
Owner XIAMEN UNIV