A kind of synthetic method of cis-jasmone
Through a simplified step-by-step process, the synthesis process efficiency and product collection of cis jasminone are successfully improved by using reactants such as 1,4-dichlorobutene, methyl magnesium chloride, 2,5-hexanedione and sodium hydroxide. The problem of long process, low yield and difficult waste disposal in the existing methods is solved.
Patent Information
- Application Number
- CN202111541400.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2021-12-16
- Publication Date
- 2024-12-06
- Estimated Expiration
- 2041-12-16
AI Technical Summary
The existing cis jasmonone synthesis method has a long process route, low product yield, large amount of 'three wastes' and difficult to deal with.
1,4-dichlorobutene and methylmagnesium chloride were used to react with methyl magnesium chloride to produce 1-chloro-2-pentene, followed by reaction with 2,5-hexanedione and sodium hydroxide to produce 3-methyl-2-cyclopentene- 1-one, and finally reacts with ethanol and sodium hydroxide to obtain cis jasminone through step-by-step process.
The process route is simplified, the reaction selectivity and conversion rate are improved, the product yield is improved, and the production cost is reduced.
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of organic synthesis, relates to the synthesis of a fragrance, and specifically relates to a synthesis method of cis-jasmone. Background Art
[0002] Cis-jasmone, scientific name 3-methyl-2-(2-pentenyl)-2-cyclopenten-1-one, is a colorless to light yellow oily liquid, slightly soluble in water, soluble in ethanol, ether and carbon tetrachloride. Cis-jasmone exists naturally in jasmine, mint, pepper, spearmint, longevity flower, bergamot and tea, with good diffusion of floral fragrance and elegant jasmine aroma. It is mainly used as the fragrance base of jasmine spices, widely used in jasmine-flavored daily chemical flavors, as well as a variety of edible flavors such as jasmine tea, strawberry, pineapple and mint-flavored edible flavors.
[0003] There are many methods for synthesizing cis-jasmone, such as: 1. Cyclopenten-2-one is used as a raw material, and first sulfonated with sodium benzenesulfinate at the β position to obtain 3-sulfonylcyclopentanone, and then condensed with ethylene glycol under acidic conditions to obtain ketal, and then olefination of the β side chain is carried out, and after acidification, cis-jasmone is obtained by aldol condensation. 2. Using 2-methylfuran as a raw material, first condensed with acrolein under alkaline conditions to obtain 3-(2-methyl-5-furanyl) propanal, and then Wittig reaction to generate 2-methyl-5-(3-hexenyl) furan, and then opened under acidic conditions to obtain undecenedione, and finally condensed under alkaline conditions to obtain cis-jasmone. 3. Using furfural as raw material, firstly react with cis-2-pentenylmagnesium chloride to undergo Grignard reaction, then undergo catalytic isomerization after acidification to generate cis-2-pentenyl-3-hydroxy-4-cyclopentenone, then hydrogenate and reduce it to cis-2-pentenyl-2-cyclopentenone under acidic conditions, and finally undergo methylation reaction with iodomethane to obtain cis-jasmone. All of the above methods have the problems of long synthetic process route, low product yield, large amount of "three wastes" and difficulty in treatment. Summary of the invention
[0004] In view of the deficiencies in the prior art, the object of the present invention is to provide a method for synthesizing cis-jasmone, which has a short process route, high reaction selectivity and conversion rate, high product yield and low cost.
[0005] The present invention is achieved through the following technical solutions:
[0006] A method for synthesizing cis-jasmone comprises the following steps:
[0007] Step 1: Add 1,4-dichlorobutene and THF into a reactor in proportion, stir and heat, dissolve methylmagnesium chloride in THF to form a THF solution and add it dropwise to the reactor, control the temperature and react after the addition is complete, when the content of 1,4-dichlorobutene is less than 1%, the reaction is terminated, quench and hydrolyze with a saturated ammonium chloride solution, add water to dissolve the salt, separate the organic phase, first recover the solvent THF at normal pressure, and then perform vacuum distillation to obtain the intermediate product 1-chloro-2-pentene;
[0008] Step 2: Add a certain proportion of 2,5-hexanedione and dibromomethane into the reactor, stir, add sodium hydroxide solution dropwise, heat and reflux to react until the content of 2,5-hexanedione is less than 1% as the reaction end point, cool, neutralize and wash, and first recover the solvent dibromomethane from the separated organic phase under normal pressure, and then perform vacuum distillation to obtain the intermediate product 3-methyl-2-cyclopentene-1-one;
[0009] Step 3, the 1-chloro-2-pentene obtained in step 1 and the 3-methyl-2-cyclopentene-1-one obtained in step 2 are put into a reactor in proportion, ethanol and sodium hydroxide are added, stirred, and the temperature is controlled to react. When the content of 3-methyl-2-cyclopentene-1-one is less than 1%, the reaction end point is reached, ethanol is first recovered under normal pressure, then neutralized and washed, and the organic phase is subjected to reduced pressure distillation to obtain the cis-jasmone product.
[0010] The reaction equation is as follows:
[0011] .
[0012] A further improvement of the present invention is:
[0013] In step 1, the molar ratio of 1,4-dichlorobutene to methylmagnesium chloride is 1:1.1-1.3; 1,4-dichlorobutene and THF are added into the reactor at a mass ratio of 1:3; and the mass concentration of methylmagnesium chloride in the THF solution is 25%.
[0014] Furthermore, in step 1, the 1,4-dichlorobutene is cis-1,4-dichlorobutene.
[0015] Furthermore, in step 1, the temperature of the temperature-controlled reaction is 20°C to 25°C.
[0016] Furthermore, in step 1, the recovered solvent THF can be reused.
[0017] Furthermore, in step 2, the mass ratio of the 2,5-hexanedione to dibromomethane is 1:3; the molar ratio of the 2,5-hexanedione to the sodium hydroxide in the sodium hydroxide solution is 1:1; and the mass concentration of the sodium hydroxide is 10%.
[0018] Furthermore, in step 2, the recovered solvent dibromomethane can be reused.
[0019] Furthermore, in step three, the molar ratio of 1-chloro-2-pentene to 3-methyl-2-cyclopentene-1-one is 1.1-1.3:1; the mass ratio of 3-methyl-2-cyclopentene-1-one to ethanol is 1:3; and the mass ratio of 3-methyl-2-cyclopentene-1-one to sodium hydroxide is 1:0.5.
[0020] Furthermore, in step three, the temperature of the temperature-controlled reaction is 30°C to 40°C.
[0021] Furthermore, in step three, the recovered solvent ethanol can be reused.
[0022] The beneficial effects of the present invention are:
[0023] Compared with other synthesis methods, the present invention has the advantages of short process route, high reaction selectivity and conversion rate, high product yield, low cost and the like. DETAILED DESCRIPTION
[0024] Example 1
[0025] Put 125g (1 mol) of 1,4-dichlorobutene and 375g of THF into the reactor, stir and heat to 20°C, slowly drop 328g (1.1 mol) of methylmagnesium chloride (25% THF solution), control the temperature at 20°C to 25°C and stir to react, and the reaction end point is when the content of 1,4-dichlorobutene is less than 1%. Add saturated ammonium chloride solution to quench the hydrolysis, then add water to dissolve the salt, separate the organic phase, first recover the solvent THF at normal pressure (reuse), and then reduce the pressure to distill to obtain the intermediate product 1-chloro-2-pentene. The effective amount of the product is 91g, and the yield is 87.1%.
[0026] Put 57g (0.5mol) of 2,5-hexanedione and 171g of dibromomethane into the reactor, stir, add 200g (0.5mol) of 10% sodium hydroxide solution, heat and reflux to react until the content of 2,5-hexanedione is less than 1%, which is the end point of the reaction. Cool, neutralize and wash, first recover the solvent dibromomethane (reuse) at normal pressure from the separated organic phase, and then reduce the pressure to distill to obtain the intermediate product 3-methyl-2-cyclopentene-1-one. The effective amount of the product is 87g, and the yield is 90.6%.
[0027] In the reactor, 115g (1.1mol) of the intermediate product 1-chloro-2-pentene, 96g (1mol) of the intermediate product 3-methyl-2-cyclopentene-1-one, 288g of ethanol, and 48g of sodium hydroxide were sequentially added, stirred and heated, and the temperature was controlled at 30°C to 40°C for reaction. When the content of 3-methyl-2-cyclopentene-1-one was less than 1%, the reaction end point was reached. Ethanol was first recovered at normal pressure (repeated use), then neutralized and washed, and the organic phase was vacuum distilled to obtain the cis-jasmone product. The effective amount of the product was 129g, and the yield was 78.7%.
[0028] Example 2
[0029] Put 125g (1 mol) of 1,4-dichlorobutene and 375g of THF into the reactor, stir and heat to 20°C, slowly drop 358g (1.2 mol) of methylmagnesium chloride (25% THF solution), control the temperature at 20°C to 25°C and stir to react, and the reaction end point is when the content of 1,4-dichlorobutene is less than 1%. Add saturated ammonium chloride solution to quench the hydrolysis, then add water to dissolve the salt, separate the organic phase, first recover the solvent THF at normal pressure (reuse), and then reduce the pressure to distill to obtain the intermediate product 1-chloro-2-pentene. The effective amount of the product is 95g, and the yield is 90.9%.
[0030] Put 114g (1 mol) of 2,5-hexanedione and 342g of dibromomethane into the reactor, stir, add 400g (1 mol) of 10% sodium hydroxide solution, heat and reflux to react until the content of 2,5-hexanedione is less than 1%, which is the end point of the reaction. Cool, neutralize and wash, first recover the solvent dibromomethane (reuse) at normal pressure from the separated organic phase, and then reduce the pressure to distill to obtain the intermediate product 3-methyl-2-cyclopentene-1-one. The effective amount of the product is 88g, and the yield is 91.7%.
[0031] In the reactor, 125g (1.2mol) of the intermediate product 1-chloro-2-pentene, 96g (1mol) of the intermediate product 3-methyl-2-cyclopentene-1-one, 288g of ethanol, and 48g of sodium hydroxide were sequentially added, stirred and heated, and the temperature was controlled at 30°C to 40°C for reaction. When the content of 3-methyl-2-cyclopentene-1-one was less than 1%, the reaction end point was reached. Ethanol was first recovered at normal pressure (repeated use), then neutralized and washed, and the organic phase was vacuum distilled to obtain the cis-jasmone product. The effective amount of the product was 132g, and the yield was 80.5%.
[0032] Example 3
[0033] Put 125g (1 mol) of 1,4-dichlorobutene and 375g of THF into the reactor, stir and heat to 20°C, slowly drop 388g (1.3 mol) of methylmagnesium chloride (25% THF solution), control the temperature at 20°C to 25°C and stir to react, and the reaction end point is when the content of 1,4-dichlorobutene is less than 1%. Add saturated ammonium chloride solution to quench the hydrolysis, then add water to dissolve the salt, separate the organic phase, first recover the solvent THF at normal pressure (reuse), and then reduce the pressure to distill to obtain the intermediate product 1-chloro-2-pentene. The effective amount of the product is 92g, and the yield is 88.1%.
[0034] Put 171g (1.5mol) of 2,5-hexanedione and 513g of dibromomethane into the reactor, stir, add 600g (1.5mol) of 10% sodium hydroxide solution, heat and reflux to react until the content of 2,5-hexanedione is less than 1%, which is the end point of the reaction. Cool, neutralize and wash, first recover the solvent dibromomethane (reuse) at normal pressure from the separated organic phase, and then reduce the pressure to distill to obtain the intermediate product 3-methyl-2-cyclopentene-1-one. The effective amount of the product is 86g, and the yield is 89.6%.
[0035] In the reactor, 136g (1.3mol) of the intermediate product 1-chloro-2-pentene, 96g (1mol) of the intermediate product 3-methyl-2-cyclopentene-1-one, 288g of ethanol, and 48g of sodium hydroxide were sequentially added, stirred and heated, and the temperature was controlled at 30°C to 40°C for reaction. When the content of 3-methyl-2-cyclopentene-1-one was less than 1%, the reaction end point was reached. Ethanol was first recovered at normal pressure (repeated use), then neutralized and washed, and the organic phase was vacuum distilled to obtain the cis-jasmone product. The effective amount of the product was 128g, and the yield was 78.1%.
Claims
1. A method for synthesizing cis-jasmone, characterized in that: The following steps are involved: Step 1: Add 1,4-dichlorobutene and THF into a reactor in proportion, stir and heat, dissolve methylmagnesium chloride in THF to form a THF solution and add it dropwise to the reactor, control the temperature and react after the addition is complete, when the content of 1,4-dichlorobutene is less than 1%, the reaction is terminated, quench and hydrolyze with a saturated ammonium chloride solution, add water to dissolve the salt, separate the organic phase, first recover the solvent THF at normal pressure, and then perform vacuum distillation to obtain the intermediate product 1-chloro-2-pentene; Step 2: Add a certain proportion of 2,5-hexanedione and dibromomethane into the reactor, stir, add sodium hydroxide solution dropwise, heat and reflux to react until the content of 2,5-hexanedione is less than 1% as the reaction end point, cool, neutralize and wash, and first recover the solvent dibromomethane from the separated organic phase under normal pressure, and then perform vacuum distillation to obtain the intermediate product 3-methyl-2-cyclopentene-1-one; Step 3, the 1-chloro-2-pentene obtained in step 1 and the 3-methyl-2-cyclopentene-1-one obtained in step 2 are put into a reactor in proportion, ethanol and sodium hydroxide are added, stirred, and the temperature is controlled to react. When the content of 3-methyl-2-cyclopentene-1-one is less than 1%, the reaction end point is reached, ethanol is first recovered under normal pressure, then neutralized and washed, and the organic phase is subjected to vacuum distillation to obtain a cis-jasmone product; In step 1, the molar ratio of 1,4-dichlorobutene to methylmagnesium chloride is 1:1.1-1.3; 1,4-dichlorobutene and THF are added to the reactor at a mass ratio of 1:3; the mass concentration of methylmagnesium chloride in the THF solution is 25%; the temperature of the temperature-controlled reaction is 20°C-25°C; In step three, the molar ratio of 1-chloro-2-pentene to 3-methyl-2-cyclopentene-1-one is 1.1-1.3:1; the mass ratio of 3-methyl-2-cyclopentene-1-one to ethanol is 1:3; the mass ratio of 3-methyl-2-cyclopentene-1-one to sodium hydroxide is 1:0.5; and the temperature control reaction temperature is 30°C-40°C.
2. A method for synthesizing cis-jasmone according to claim 1, characterized in that: In step 1, the 1,4-dichlorobutene is cis-1,4-dichlorobutene.
3. A method for synthesizing cis-jasmone according to claim 1, characterized in that: In step 1, the recovered solvent THF can be reused.
4. The method for synthesizing cis-jasmone according to claim 1, characterized in that: In step 2, the mass ratio of the 2,5-hexanedione to dibromomethane is 1:3; the molar ratio of the 2,5-hexanedione to the sodium hydroxide in the sodium hydroxide solution is 1:1; and the mass concentration of the sodium hydroxide is 10%.
5. The method for synthesizing cis-jasmone according to claim 1, characterized in that: In step 2, the recovered solvent dibromomethane can be reused.
6. The method for synthesizing cis-jasmone according to claim 1, characterized in that: In step three, the recovered solvent ethanol can be reused.