CN108623460A - A kind of synthetic method of 7- chloro-2-oxoheptanoates - Google Patents
A kind of synthetic method of 7- chloro-2-oxoheptanoates Download PDFInfo
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- CN108623460A CN108623460A CN201810607950.9A CN201810607950A CN108623460A CN 108623460 A CN108623460 A CN 108623460A CN 201810607950 A CN201810607950 A CN 201810607950A CN 108623460 A CN108623460 A CN 108623460A
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C67/00—Preparation of carboxylic acid esters
- C07C67/30—Preparation of carboxylic acid esters by modifying the acid moiety of the ester, such modification not being an introduction of an ester group
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- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J31/00—Catalysts comprising hydrides, coordination complexes or organic compounds
- B01J31/02—Catalysts comprising hydrides, coordination complexes or organic compounds containing organic compounds or metal hydrides
- B01J31/06—Catalysts comprising hydrides, coordination complexes or organic compounds containing organic compounds or metal hydrides containing polymers
- B01J31/063—Polymers comprising a characteristic microstructure
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Abstract
The invention discloses a kind of synthetic method of 7 chlorine, 2 oxoheptanoate, Mg, 1 bromine, 5 chloropentane, tetrahydrofuran, hydrochloric acid, NaHC03, Chloropolystyrene resin, imidazoles, acetonitrile, diethy-aceto oxalate be primary raw material, the synthesis technology of the present invention obtains 7 chlorine, 2 oxoheptanoate under the action of immobilized ionic catalyst PSIM MgBr using diethy-aceto oxalate and 1 bromine, 5 chloropentane by addition and hydrolysis, compared to traditional synthetic method, raw material is reacted by activation of catalyst directly prepares 7 chlorine, 2 oxoheptanoate, so that yield increases substantially, technological process and production cost are reduced.
Description
Technical field
The present invention relates to a kind of synthetic methods of 7- chloro-2-oxoheptanoates, belong to chemical industry synthesis field.
Background technology
7- chloro-2-oxoheptanoates are important chemical and medicine industry intermediate, synthesize 7- chloro-2-oxoheptanoates at present
Method present in major defect be that synthesis condition is more harsh, production cost is high, present invention research 7- chloro-2-oxo-heptanoic acids
The synthesis technology of ethyl ester explores the synthetic method for improving intermediate yield.
Invention content
The purpose of the present invention is to provide a kind of synthetic methods of 7- chloro-2-oxoheptanoates, and this method is in optimization item
It can be catalyzed the reaction of diethy-aceto oxalate and the bromo- 5- chloropentanes of 1- under part, there is higher product yield.
A kind of synthetic method of 7- chloro-2-oxoheptanoates, it is characterised in that this approach includes the following steps：
Step 1, dry N2Under protection, in four mouthfuls of burnings equipped with condenser pipe, thermometer, blender and 50ml constant pressure funnels
The mixed liquor of 7.3g diethy-aceto oxalates, 9.3g1- bromo- 5- chloropentanes and 30m1 tetrahydrofurans is added in bottle；
Step 2, under the conditions of -25 DEG C, rapidly join 1.0g PSIM-MgBr, reaction temperature control kept during dropwise reaction
At -10 DEG C or so, after being added dropwise, the reaction was continued 1h；
Step 3 is hydrolyzed with the hydrochloric acid of 15ml concentration 4M, ensures that reaction temperature is 0 DEG C or less during acid hydrolysis.It separates organic
Layer, water layer are extracted with dichloromethane, are used in combination the full sodium chloride solution that closes to wash, NaHS0 is added3It is full to close solution oscillation；
Step 4, concussion finish, organic layer and water layer saturation NaHC03Solution neutralizes, and organic layer rotation steams tetrahydrofuran, closes
And organic layer and with saturation NaHC03It neutralizes, NaHS03Washing, then washed with NaCl until neutrality, is evaporated off solvent, rectification under vacuum obtains
To 7- chloro-2-oxoheptanoates.
The immobilized ionic catalyst preparation methods of the PSIM-MgBr are as follows：
Chloropolystyrene resin is dried in vacuo 12 h by step 1 at 80 DEG C, the Chloropolystyrene tree after taking l0g to dry
Fat, 3.6g imidazoles react 8h with 70ml acetonitriles at 80 DEG C；
Step 2, reaction are filtered after completing, and are rinsed using ethyl acetate, water, methanol, then are carried out very at 80 DEG C
Sky is dry, and obtained solid particle is named as PSIM；
Step 3, dry N2Under protection, in the 100m1 equipped with thermometer, condenser pipe, blender and 50ml constant pressure funnels
10gPSIM, 1.44gMg and 15m1 tetrahydrofuran are added in four-hole boiling flask；
Under step 4, magnetic agitation plus 2 iodine are as initiator, reaction to be triggered；
Step 5, the mixed solution that 9.3g1- bromo- 5- chloropentanes and 25m1 tetrahydrofurans is slowly added dropwise, use ice water in reaction process
Bath control temperature is no more than 30 DEG C, after magnesium has reacted, obtains immobilized ionic catalyst PSIM-MgBr.
Advantageous effect：The present invention provides a kind of synthetic method of 7- chloro-2-oxoheptanoates, diethy-aceto oxalate and 1-
Bromo- 5- chloropentanes obtain 7- chloro-2-oxos heptan under the action of immobilized ionic catalyst PSIM-MgBr by addition and hydrolysis
Acetoacetic ester, alkyl halide is reacted with magnesium chips first in the preparation process of catalyst generates Grignard Reagent, due to the electronegativity of metal
It is generally smaller than carbon atom；Therefore, carbon-halogen bond is usually polar covalent bond, and is high degree of polarization, and metallic atom is carrying part just
Charge, and the carbon atom being attached thereto carries partial negative charge, carbon-halogen bond is easier to be broken, and shows activity.Anti-
During answering, the alkyl in Grignard Reagent is moved on to from magnesium on carbonylic carbon atom with a pair of of linkage electron, and nucleophilic atom is carbon
Atom, is stronger nucleopilic reagent, and obtained addition compound product can be obtained target product through hydrolysis；Acid is used at a lower temperature
When hydrolysis, the activity that hydrogen migrates can weaken significantly, cause enol form product to reduce, therefore when lower temperature reacts, have
Conducive to the generation of keto-acid product.
Specific implementation mode
Embodiment 1
A kind of synthetic method of 7- chloro-2-oxoheptanoates, it is characterised in that this approach includes the following steps：
Step 1, dry N2Under protection, in four mouthfuls of burnings equipped with condenser pipe, thermometer, blender and 50ml constant pressure funnels
The mixed liquor of 7.3g diethy-aceto oxalates, 9.3g1- bromo- 5- chloropentanes and 30m1 tetrahydrofurans is added in bottle；
Step 2, under the conditions of -25 DEG C, rapidly join 1.0g PSIM-MgBr, reaction temperature control kept during dropwise reaction
At -10 DEG C or so, after being added dropwise, the reaction was continued 1h；
Step 3 is hydrolyzed with the hydrochloric acid of 15ml concentration 4M, ensures that reaction temperature is 0 DEG C or less during acid hydrolysis.It separates organic
Layer, water layer are extracted with dichloromethane, are used in combination the full sodium chloride solution that closes to wash, NaHS0 is added3It is full to close solution oscillation；
Step 4, concussion finish, organic layer and water layer saturation NaHC03Solution neutralizes, and organic layer rotation steams tetrahydrofuran, closes
And organic layer and with saturation NaHC03It neutralizes, NaHS03Washing, then washed with NaCl until neutrality, is evaporated off solvent, rectification under vacuum obtains
To 7- chloro-2-oxoheptanoates.
The immobilized ionic catalyst preparation methods of the PSIM-MgBr are as follows：
Chloropolystyrene resin is dried in vacuo 12 h by step 1 at 80 DEG C, the Chloropolystyrene tree after taking l0g to dry
Fat, 3.6g imidazoles react 8h with 70ml acetonitriles at 80 DEG C；
Step 2, reaction are filtered after completing, and are rinsed using ethyl acetate, water, methanol, then are carried out very at 80 DEG C
Sky is dry, and obtained solid particle is named as PSIM；
Step 3, dry N2Under protection, in the 100m1 equipped with thermometer, condenser pipe, blender and 50ml constant pressure funnels
10gPSIM, 1.44gMg and 15m1 tetrahydrofuran are added in four-hole boiling flask；
Under step 4, magnetic agitation plus 2 iodine are as initiator, reaction to be triggered；
Step 5, the mixed solution that 9.3g1- bromo- 5- chloropentanes and 25m1 tetrahydrofurans is slowly added dropwise, use ice water in reaction process
Bath control temperature is no more than 30 DEG C, after magnesium has reacted, obtains immobilized ionic catalyst PSIM-MgBr.
Embodiment 2
Step 1, dry N2Under protection, in four mouthfuls of burnings equipped with condenser pipe, thermometer, blender and 50ml constant pressure funnels
The mixed liquor of 5.3g diethy-aceto oxalates, 9.3g1- bromo- 5- chloropentanes and 30m1 tetrahydrofurans is added in bottle；Remaining step is same
Embodiment 1.
Embodiment 3
Step 1, dry N2Under protection, in four mouthfuls of burnings equipped with condenser pipe, thermometer, blender and 50ml constant pressure funnels
The mixed liquor of 3.3g diethy-aceto oxalates, 9.3g1- bromo- 5- chloropentanes and 30m1 tetrahydrofurans is added in bottle；Remaining step is same
Embodiment 1.
Embodiment 4
Step 1, dry N2Under protection, in four mouthfuls of burnings equipped with condenser pipe, thermometer, blender and 50ml constant pressure funnels
The mixed liquor of 10.3g diethy-aceto oxalates, 9.3g1- bromo- 5- chloropentanes and 30m1 tetrahydrofurans is added in bottle；Remaining step
With embodiment 1.
Embodiment 5
Step 1, dry N2Under protection, in four mouthfuls of burnings equipped with condenser pipe, thermometer, blender and 50ml constant pressure funnels
The mixed liquor of 13.3g diethy-aceto oxalates, 9.3g1- bromo- 5- chloropentanes and 30m1 tetrahydrofurans is added in bottle；Remaining step
With embodiment 1.
Embodiment 6
Step 1, dry N2Under protection, in four mouthfuls of burnings equipped with condenser pipe, thermometer, blender and 50ml constant pressure funnels
The mixed liquor of 17.3g diethy-aceto oxalates, 9.3g1- bromo- 5- chloropentanes and 30m1 tetrahydrofurans is added in bottle；Remaining step
With embodiment 1.
Embodiment 7
Step 1, dry N2Under protection, in four mouthfuls of burnings equipped with condenser pipe, thermometer, blender and 50ml constant pressure funnels
The mixed liquor of 7.3g diethy-aceto oxalates, 14.3g1- bromo- 5- chloropentanes and 30m1 tetrahydrofurans is added in bottle；Remaining step
With embodiment 1.
Embodiment 8
Step 1, dry N2Under protection, in four mouthfuls of burnings equipped with condenser pipe, thermometer, blender and 50ml constant pressure funnels
The mixed liquor of 7.3g diethy-aceto oxalates, 19.3g1- bromo- 5- chloropentanes and 30m1 tetrahydrofurans is added in bottle；Remaining step
With embodiment 1.
Embodiment 9
Step 1, dry N2Under protection, in four mouthfuls of burnings equipped with condenser pipe, thermometer, blender and 50ml constant pressure funnels
The mixed liquor of 7.3g diethy-aceto oxalates, 24.3g1- bromo- 5- chloropentanes and 30m1 tetrahydrofurans is added in bottle；Remaining step
With embodiment 1.
Embodiment 10
Step 1, dry N2Under protection, in four mouthfuls of burnings equipped with condenser pipe, thermometer, blender and 50ml constant pressure funnels
The mixed liquor of 7.3g diethy-aceto oxalates, 29.3g1- bromo- 5- chloropentanes and 30m1 tetrahydrofurans is added in bottle；Remaining step
With embodiment 1.
Reference examples 1
It is with 1 difference of embodiment：In the synthesis step 2 of intermediate, the PSIM of equivalent is added as catalyst, remaining step
It is identical with embodiment 1.
Reference examples 2
It is with 1 difference of embodiment：In the synthesis step 2 of intermediate, catalyst PSIM-MgBr is not added, remaining step
It is identical with embodiment 1.
Reference examples 3
It is with 1 difference of embodiment：In the synthesis step 1 of catalyst, Chloropolystyrene resin, imidazoles mass ratio are 1：1,
Remaining step is identical with embodiment 1.
Reference examples 4
It is with 1 difference of embodiment：In the synthesis step 1 of catalyst, Chloropolystyrene resin, imidazoles mass ratio are 25：
9, remaining step is identical with embodiment 1.
Reference examples 5
It is with 1 difference of embodiment：In the synthesis step 1 of catalyst, replace chlorinated polyphenyl second with the styrene resin of equivalent
Olefine resin, remaining step are identical with embodiment 1.
Reference examples 6
It is with 1 difference of embodiment：In the synthesis step 1 of catalyst, Chloropolystyrene resin is not added, remaining step
It is identical with embodiment 1.
Reference examples 7
It is with 1 difference of embodiment：In the synthesis step 3 of catalyst, PSIM, Mg mass ratio are 7:50, remaining step and reality
It is identical to apply example 1.
Reference examples 8
It is with 1 difference of embodiment：In the synthesis step 3 of catalyst, PSIM, Mg mass ratio are 1:1, remaining step with implement
Example 1 is identical.
Reference examples 9
It is with 1 difference of embodiment：In the synthesis step 5 of catalyst, replace the bromo- 5- chloropentanes of 1- with the vinyl chloride of equivalent,
Remaining step is identical with embodiment 1.
Reference examples 10
It is with 1 difference of embodiment：In the synthesis step 5 of catalyst, replace the bromo- 5- chlorine of 1- with 1, the 2- Bromofumes of equivalent
Pentane, remaining step are identical with embodiment 1.
It is as shown in the table for reaction result under embodiment and reference examples different condition
The experimental results showed that catalyst imitates the synthetic reaction of diethy-aceto oxalate and the bromo- 5- chloropentanes of 1- with good catalysis
Fruit, in one timing of reaction condition, intermediate yield is higher, and catalytic performance is better, otherwise poorer；The bromo- 5- chlorine of diethyl phthalate, 1- penta
Alkane mass ratio is 7：When 9, other dispensings are fixed, and synthetic effect is best, with embodiment 1 the difference lies in that embodiment 2 is to embodiment
10 change the dosage and proportioning of primary raw material diethyl phthalate, the bromo- 5- chloropentanes of 1- respectively, in spite of certain effect, but not strictly according to the facts
Apply 1 high income of example；Reference examples 1 to reference examples 2 no longer use PSIM-MgBr to replace as catalyst and with PSIM, other steps are complete
It is exactly the same, cause product yield to be substantially reduced, illustrates that ion is immobilized very big on the influence of the product of reaction；Reference examples 3 are to reference examples 6
Chloropolystyrene resin is not added and changes the proportioning with imidazoles, and effect is still bad, illustrates Chloropolystyrene resin
And its dosage is very crucial；Reference examples 7 to reference examples 8 change PSIM, Mg mass ratio, are catalyzed the variation with obvious effects of reaction, say
Bright PSIM, Mg mass ratio is 50:7 pairs of catalyst improvements are preferable；Reference examples 9 to the equivalent of reference examples 10 1,2- dibromo second
Alkane and vinyl chloride replace the bromo- 5- chloropentanes of 1-, the activity of catalyst to reduce, and reaction effect is obviously deteriorated, and product yield obviously drops
It is low；Therefore there is excellent catalytic effect to the synthetic reaction of intermediate senecioic acid methyl esters using the catalyst of the present invention.
Claims (2)
1. a kind of synthetic method of 7- chloro-2-oxoheptanoates, it is characterised in that this approach includes the following steps：
Step 1, dry N2Under protection, in four mouthfuls of burnings equipped with condenser pipe, thermometer, blender and 50ml constant pressure funnels
The mixed liquor of 7.3g diethy-aceto oxalates, 9.3g1- bromo- 5- chloropentanes and 30m1 tetrahydrofurans is added in bottle；
Step 2, under the conditions of -25 DEG C, rapidly join 1.0g PSIM-MgBr, reaction temperature control kept during dropwise reaction
At -10 DEG C or so, after being added dropwise, the reaction was continued 1h；
Step 3 is hydrolyzed with the hydrochloric acid of 15ml concentration 4M, ensures that reaction temperature is 0 DEG C or less during acid hydrolysis；
Organic layer is separated, water layer is extracted with dichloromethane, is used in combination the full sodium chloride solution that closes to wash, NaHS0 is added3The full solution that closes shakes
It swings；
Step 4, concussion finish, organic layer and water layer saturation NaHC03Solution neutralizes, and organic layer rotation steams tetrahydrofuran, closes
And organic layer and with saturation NaHC03It neutralizes, NaHS03Washing, then washed with NaCl until neutrality, is evaporated off solvent, rectification under vacuum obtains
To 7- chloro-2-oxoheptanoates.
2. a kind of synthetic method of 7- chloro-2-oxoheptanoates according to claim 1, it is characterised in that
The immobilized ionic catalyst preparation methods of the PSIM-MgBr are as follows：
Chloropolystyrene resin is dried in vacuo 12 h by step 1 at 80 DEG C, the Chloropolystyrene tree after taking l0g to dry
Fat, 3.6g imidazoles react 8h with 70ml acetonitriles at 80 DEG C；
Step 2, reaction are filtered after completing, and are rinsed using ethyl acetate, water, methanol, then are carried out very at 80 DEG C
Sky is dry, and obtained solid particle is named as PSIM；
Step 3, dry N2Under protection, in the 100m1 equipped with thermometer, condenser pipe, blender and 50ml constant pressure funnels
10gPSIM, 1.44gMg and 15m1 tetrahydrofuran are added in four-hole boiling flask；
Under step 4, magnetic agitation plus 2 iodine are as initiator, reaction to be triggered；
Step 5, the mixed solution that 9.3g1- bromo- 5- chloropentanes and 25m1 tetrahydrofurans is slowly added dropwise, use ice water in reaction process
Bath control temperature is no more than 30 DEG C, after magnesium has reacted, obtains immobilized ionic catalyst PSIM-MgBr.
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Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2003087029A1 (en) * | 2002-04-18 | 2003-10-23 | Sumika Fine Chemicals Co., Ltd. | PROCESS FOR PRODUCING α-HYDROXYCARBOXYLIC ACID COMPOUND |
| CN101265187A (en) * | 2008-04-21 | 2008-09-17 | 太仓市浦源化工有限公司 | Method for preparing ethyl 7-chloro-2-oxyheptanoate |
-
2018
- 2018-06-13 CN CN201810607950.9A patent/CN108623460A/en not_active Withdrawn
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2003087029A1 (en) * | 2002-04-18 | 2003-10-23 | Sumika Fine Chemicals Co., Ltd. | PROCESS FOR PRODUCING α-HYDROXYCARBOXYLIC ACID COMPOUND |
| CN101265187A (en) * | 2008-04-21 | 2008-09-17 | 太仓市浦源化工有限公司 | Method for preparing ethyl 7-chloro-2-oxyheptanoate |
Non-Patent Citations (2)
| Title |
|---|
| 仲崇超: "西司他丁中间体合成工艺研究", 《中国优秀硕士学位论文全文数据库 工程科技Ⅰ辑》 * |
| 王一: "固载化离子液体催化合成碳酸二甲酯和乙二醇", 《广州化工》 * |
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