Novel preparation method of cyclopropyl methyl ketone

Abstract

The invention discloses a novel preparation method of cyclopropyl methyl ketone. The preparation method comprises the following steps: an ionic liquid is added to a microwave reactor, stirring is started, and microwave heating is started to increase the temperature to 100-140 DEG C; 2-acetylbutyrolactone is added slowly and continuously at 100-140 DEG C, a catalytic cracking reaction of the ionicliquid is promoted by microwaves, and a cracked product cyclopropyl methyl ketone is withdrawn through a distillation column continuously. The ionic liquid is promoted by the microwaves for catalyticcracking of the raw material 2-acetylbutyrolactone, high selectivity is realized when the reaction is performed under the conditions, impurities are almost avoided in the reaction, the content of cyclopropyl methyl ketone obtained with the method is higher than 99% and the total reaction yield is higher than 98%, which are both far higher than those obtained in the traditional method and in literature report. Production of three wastes in the reaction process is completely avoided, and the environment is protected; danger probably caused in a high-temperature production process is avoided, higher safety is realized, and operation efficiency can be increased.

Description

technical field

[0001] The invention belongs to the technical field of organic chemistry, and in particular relates to a new preparation method of cyclopropanone. Background technique

[0002] Cyclopropanone, CAS number: 765-43-5, molecular formula: C5H8O. Cyclopropanone is an important organic raw material and intermediate. In medicine, it is mainly used in the synthesis of anti-AIDS drugs Efluverenz and Ilremin; in pesticides, it is mainly used in the synthesis of fungicides cyprodinil and cyproconazole.

[0003] There are many ways to synthesize cyclopropanone, among which the raw material α-acetyl-γ-butyrolactone is more competitive. The raw material α-acetyl-γ-butyrolactone can undergo a hydrolysis halogenation reaction to generate a halogenated pentanone, and then undergo a ring closure reaction to obtain the product cyclopropanone. This route has too many wastes, serious pollution and high cost.

[0004] U.S. Patent No. 5,254,739 discloses a new method. The raw ma...

Examples

Embodiment 1

[0023] 1) In the microwave reactor, add 200 g of 1-butyl-3-methylimidazolium chloride salt ionic liquid, start stirring, start microwave heating, and raise the temperature to 140°C;

[0024] 2) At a temperature of 140°C, slowly and continuously add α-acetyl-γ-butyrolactone, microwaves promote the catalyzed cracking reaction of the ionic liquid, and continuously extract the cracked product cyclopropanone through the rectification tower. The raw material addition rate was 10 g / min.

[0025] 3) After the raw material feeding is completed, the distillation is continued for 1 hour to collect the complete product cyclopropanone. After the reaction, the obtained ionic liquid can be directly used for the preparation of the next batch of cyclopropanone products without any treatment.

[0026] The content of the collected cyclopropanone was 99.10%, and the total molar yield of the reaction was 98.2%.

Embodiment 2

[0028] 1) In the microwave reactor, add 200 g of 1-ethyl-3-methylimidazolium bromide salt ionic liquid, start stirring, start microwave heating, and raise the temperature to 100°C;

[0029] 2) At a temperature of 100°C, α-acetyl-γ-butyrolactone is added slowly and continuously, microwaves promote the catalyzed cracking reaction of the ionic liquid, and at the same time, the cracked product cyclopropanone is continuously extracted through the rectification tower. The feed rate was 1.0 g / min.

[0030] 3) After the raw material feeding is completed, continue to distill and extract for 2 hours, and collect the complete product cyclopropanone. After the reaction, the obtained ionic liquid can be directly used for the preparation of the next batch of cyclopropanone products without any treatment.

[0031] The content of the collected cyclopropanone was 99.5%, and the total molar yield of the reaction was 98.9%.

Embodiment 3

[0033] 1) In the microwave reactor, add 200 g of 1-butyl-3-methylimidazolium iodide salt ionic liquid, start stirring, start microwave heating, and raise the temperature to 120°C;

[0034] 2) At a temperature of 120°C, α-acetyl-γ-butyrolactone is added slowly and continuously, microwaves promote the catalytic cracking reaction of the ionic liquid, and at the same time, the cracking product cyclopropanone is continuously extracted through the rectification tower. The feed rate was 2.0 g / min.

[0035] 3) After the raw material feeding is completed, the distillation is continued for 1 hour to collect the complete product cyclopropanone. After the reaction, the obtained ionic liquid can be directly used for the preparation of the next batch of cyclopropanone products without any treatment.

[0036] The content of the collected cyclopropanone was 99.70%, and the total molar yield of the reaction was 99.2%.

technical field

[0001] The invention belongs to the technical field of organic chemistry, and in particular relates to a new preparation method of cyclopropanone. Background technique

[0002] Cyclopropanone, CAS number: 765-43-5, molecular formula: C5H8O. Cyclopropanone is an important organic raw material and intermediate. In medicine, it is mainly used in the synthesis of anti-AIDS drugs Efluverenz and Ilremin; in pesticides, it is mainly used in the synthesis of fungicides cyprodinil and cyproconazole.

[0003] There are many ways to synthesize cyclopropanone, among which the raw material α-acetyl-γ-butyrolactone is more competitive. The raw material α-acetyl-γ-butyrolactone can undergo a hydrolysis halogenation reaction to generate a halogenated pentanone, and then undergo a ring closure reaction to obtain the product cyclopropanone. This route has too many wastes, serious pollution and high cost.

[0004] U.S. Patent No. 5,254,739 discloses a new method. The raw ma...

Examples

Embodiment 1

[0023] 1) In the microwave reactor, add 200 g of 1-butyl-3-methylimidazolium chloride salt ionic liquid, start stirring, start microwave heating, and raise the temperature to 140°C;

[0024] 2) At a temperature of 140°C, slowly and continuously add α-acetyl-γ-butyrolactone, microwaves promote the catalyzed cracking reaction of the ionic liquid, and continuously extract the cracked product cyclopropanone through the rectification tower. The raw material addition rate was 10 g / min.

[0025] 3) After the raw material feeding is completed, the distillation is continued for 1 hour to collect the complete product cyclopropanone. After the reaction, the obtained ionic liquid can be directly used for the preparation of the next batch of cyclopropanone products without any treatment.

[0026] The content of the collected cyclopropanone was 99.10%, and the total molar yield of the reaction was 98.2%.

Embodiment 2

[0028] 1) In the microwave reactor, add 200 g of 1-ethyl-3-methylimidazolium bromide salt ionic liquid, start stirring, start microwave heating, and raise the temperature to 100°C;

[0029] 2) At a temperature of 100°C, α-acetyl-γ-butyrolactone is added slowly and continuously, microwaves promote the catalyzed cracking reaction of the ionic liquid, and at the same time, the cracked product cyclopropanone is continuously extracted through the rectification tower. The feed rate was 1.0 g / min.

[0030] 3) After the raw material feeding is completed, continue to distill and extract for 2 hours, and collect the complete product cyclopropanone. After the reaction, the obtained ionic liquid can be directly used for the preparation of the next batch of cyclopropanone products without any treatment.

[0031] The content of the collected cyclopropanone was 99.5%, and the total molar yield of the reaction was 98.9%.

Embodiment 3

[0033] 1) In the microwave reactor, add 200 g of 1-butyl-3-methylimidazolium iodide salt ionic liquid, start stirring, start microwave heating, and raise the temperature to 120°C;

[0034] 2) At a temperature of 120°C, α-acetyl-γ-butyrolactone is added slowly and continuously, microwaves promote the catalytic cracking reaction of the ionic liquid, and at the same time, the cracking product cyclopropanone is continuously extracted through the rectification tower. The feed rate was 2.0 g / min.

[0035] 3) After the raw material feeding is completed, the distillation is continued for 1 hour to collect the complete product cyclopropanone. After the reaction, the obtained ionic liquid can be directly used for the preparation of the next batch of cyclopropanone products without any treatment.

[0036] The content of the collected cyclopropanone was 99.70%, and the total molar yield of the reaction was 99.2%.

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