Method for preparing cyclopentanone
Technical Field
The invention relates to the field of organic synthesis, and particularly relates to a method for preparing cyclopentanone.
Background
Cyclopentanone, colorless transparent oily liquid, special ether and mint-like smell, is insoluble in water, soluble in alcohol and ether
Most organic solvents. The product is an important fine chemical intermediate, and is an important raw material for perfume and pharmaceutical industry. The cyclopentanone can be used for preparing jasmone, methyl dihydrojasmonate, albendanone, 2-n-hexyl cyclopentanone, 2, 3-cyclopentenopyridine, buspirone as anxiolytic and various anti-inflammatory and anti-cancer drugs, and can also be used for synthesizing pesticides, herbicides and rubber. Meanwhile, cyclopentanone is widely used as a solvent in the electronic industry because of its good solubility for various resins.
At present, the methods for preparing cyclopentanone mainly comprise the following methods:
(1) the adipic acid method mainly uses adipic acid as a raw material to prepare cyclopentanone through high-temperature decarboxylation, which is the main method for industrially producing cyclopentanone at present, but is limited by the source of the raw material and a large amount of pollutants, so that the further development of the process is limited.
(2) The preparation of cyclopentanone by using cyclopentene as a raw material, obtaining cyclopentanol through indirect hydration or direct hydration, and then preparing cyclopentanone through catalytic dehydrogenation generally comprises the steps of hydration reaction of cyclopentene, recovery of unreacted raw materials, refining of a solvent, refining of cyclopentanol, dehydrogenation and refining of cyclopentanol and the like, but has the problems of long flow path and high energy consumption.
(3) The conversion rate is not high, chlorine-containing by-products are generated, the equipment is corroded greatly, and the post-treatment is difficult.
(4) Using cyclopentene as raw material and N2O is used as an oxidant to prepare cyclopentanone, and although the yield of cyclopentanone is high, the reaction energy consumption is very high due to the adoption of conditions such as high temperature and high pressure, and the industrial development is not facilitated.
Metal Organic Frameworks (MOFs) are a class of porous materials constructed by coordination bonds between Metal ions and Organic ligands. The highly dispersed metal ions in the MOFs structure have unsaturated coordination sites, the ions with the unsaturated coordination sites can be used as catalytic active centers to participate in catalytic reaction, and meanwhile, the material has larger specific surface area and pore volume, so that the rapid reaction is facilitated.
The Fe-MIL-101 has a multi-stage mesoporous structure and a special appearance, and has a large specific surface area, so that the Fe-MIL-101 is widely applied to the fields of degradation of dyes, impurity adsorption, catalysis and the like in recent years, but the prior art does not report that the Fe-MIL-101 can be used for catalyzing cyclopentene to prepare cyclopentanone.
Disclosure of Invention
Based on solving the problems of high pollution, strong corrosion, long process, low yield, high energy consumption and the like in the process of preparing cyclopentanone in the prior art, the invention provides a method for preparing cyclopentanone, which comprises the following steps:
the method for preparing cyclopentanone is characterized in that cyclopentanone is obtained by taking cyclopentene as a raw material and Fe-MIL-101 as a catalyst in a first organic solvent and under the condition of an oxidant.
The method comprises the following operation steps of mixing and stirring cyclopentene and an organic solvent uniformly, adding a catalyst Fe-MIL-101, continuing stirring to disperse the system uniformly, introducing an oxidant into the system, and slowly heating the system to reflux for 1-3 hours to obtain cyclopentanone.
The first organic solvent is one or a mixture of ethanol, ethyl acetate, benzene, toluene, dichloromethane and tetrahydrofuran.
The oxidant is selected from oxygen or air.
The mol ratio of the cyclopentene to the catalyst is 1: 0.01-0.1.
Preferably, the method further comprises a post-treatment process, after the reaction is finished, the catalyst is filtered to remove to obtain an organic phase, the catalyst is washed by a second organic solvent to obtain a washing liquid, and the washing liquid and the organic phase are combined and rectified to obtain the target product.
The second organic solvent is one or a mixture of ethanol, ethyl acetate, benzene, toluene, dichloromethane and tetrahydrofuran.
Compared with the prior art, the invention has the following technical effects:
the Fe-MIL-101 is used as the catalyst to catalyze the cyclopentene to prepare the cyclopentanone, the used catalyst is less in dosage, and the method has the advantages of short reaction time, low energy consumption, simple post-treatment, high conversion rate of the cyclopentene, high selectivity of the cyclopentanone and the like.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present disclosure more apparent, the technical solutions of the embodiments of the present disclosure are described below clearly and completely. It is to be understood that the described embodiments are only a few embodiments of the present disclosure, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the described embodiments of the disclosure without any inventive step, are within the scope of protection of the disclosure.
Unless otherwise defined, technical or scientific terms used herein shall have the ordinary meaning as understood by one of ordinary skill in the art to which this disclosure belongs. The use of "first," "second," and similar terms in this disclosure is not intended to indicate any order, quantity, or importance, but rather is used to distinguish one element from another.
Example 1
Preparation of catalyst Fe-MIL-101
0.1mol of terephthalic acid and 0.11mol of FeCl3·6H2Dissolving O in 100mLDMF, adding 10mL of acetic acid, uniformly dispersing, preserving heat for 24h at 110 ℃, cooling to room temperature after the reaction is finished, performing suction filtration by using a suction filtration vacuum pump, repeatedly washing the obtained solid product by using DMF until the color is not changed, recrystallizing by using ethanol, and drying to obtain the solid catalyst Fe-MIL-101.
Example 2
Adding 0.1mol of cyclopentene and 20ml of ethanol into a reaction vessel in sequence, fully mixing the cyclopentene and the ethanol by using a magnetic stirrer, adding 0.001mol of Fe-MIL-101, stirring until the mixture is uniformly dispersed, introducing oxygen into the system, slowly heating the system to reflux, reacting for 1h, filtering to remove a catalyst to obtain an organic phase, washing the catalyst with ethanol for 3 times to obtain a washing solution, combining the washing solution and the organic phase, and rectifying to obtain a target product, wherein the conversion rate of the cyclopentene is 95.5%, and the selectivity of cyclopentanone is 98.1%.
Example 3
Adding 0.1mol of cyclopentene and 20ml of ethyl acetate into a reaction vessel in sequence, fully mixing the cyclopentene and the ethyl acetate by using a magnetic stirrer, adding 0.005mol of Fe-MIL-101, stirring until the mixture is uniformly dispersed, introducing oxygen into the system, slowly heating the system to reflux, reacting for 1.5h, filtering to remove the catalyst to obtain an organic phase, washing the catalyst for 3 times by using ethyl acetate to obtain a washing solution, combining the washing solution with the organic phase, and rectifying to obtain a target product, wherein the conversion rate of the cyclopentene is 97.1%, and the selectivity of cyclopentanone is 98.8%.
Example 4
Adding 0.1mol of cyclopentene and 20ml of benzene into a reaction container in sequence, fully mixing the cyclopentene and the benzene by using a magnetic stirrer, adding 0.002mol of Fe-MIL-101, stirring until the mixture is uniformly dispersed, introducing oxygen into the system, slowly heating the system to reflux, reacting for 1.5h, filtering to remove the catalyst to obtain an organic phase, washing the catalyst with ethanol for 3 times to obtain a washing solution, combining the washing solution and the organic phase, and rectifying to obtain a target product, wherein the conversion rate of the cyclopentene is 96.8%, and the selectivity of cyclopentanone is 99.1%.
Example 5
Adding 0.1mol of cyclopentene and 20ml of toluene into a reaction container in sequence, fully mixing the cyclopentene and the toluene by using a magnetic stirrer, adding 0.01mol of Fe-MIL-101, stirring until the mixture is uniformly dispersed, introducing air into the system, slowly heating the system to reflux, reacting for 2 hours, filtering to remove a catalyst to obtain an organic phase, washing the catalyst with ethanol for 3 times to obtain a washing solution, combining the washing solution and the organic phase, and rectifying to obtain a target product, wherein the conversion rate of the cyclopentene is 98.4%, and the selectivity of cyclopentanone is 99.2%.
Example 6
Adding 0.1mol of cyclopentene and 20ml of dichloromethane into a reaction container in sequence, fully mixing the cyclopentene and the dichloromethane by using a magnetic stirrer, adding 0.001mol of Fe-MIL-101, stirring until the mixture is uniformly dispersed, introducing air into the system, slowly heating the system to reflux, reacting for 3 hours, filtering to remove a catalyst to obtain an organic phase, washing the catalyst with dichloromethane for 3 times to obtain a washing solution, combining the washing solution with the organic phase, and rectifying to obtain a target product, wherein the conversion rate of the cyclopentene is 97.7%, and the selectivity of cyclopentanone is 98.2%.
Example 7
Adding 0.1mol of cyclopentene and 20ml of THF into a reaction vessel in sequence, fully mixing the cyclopentene and 20ml of THF by using a magnetic stirrer, adding 0.003mol of Fe-MIL-101, stirring until the mixture is uniformly dispersed, introducing air into the system, slowly heating the system to reflux, reacting for 2.5 hours, filtering to remove the catalyst to obtain an organic phase, washing the catalyst with ethanol for 3 times to obtain a washing solution, combining the washing solution and the organic phase, and rectifying to obtain a target product, wherein the conversion rate of the cyclopentene is 96.9%, and the selectivity of cyclopentanone is 98.9%.
Finally, it should be noted that: it should be understood that the above examples are only for clearly illustrating the present invention and are not intended to limit the embodiments. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. And obvious variations or modifications of the invention may be made without departing from the scope of the invention.