CN108947870A - A kind of preparation method of bromo sartanbiphenyl - Google Patents
A kind of preparation method of bromo sartanbiphenyl Download PDFInfo
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- CN108947870A CN108947870A CN201810813436.0A CN201810813436A CN108947870A CN 108947870 A CN108947870 A CN 108947870A CN 201810813436 A CN201810813436 A CN 201810813436A CN 108947870 A CN108947870 A CN 108947870A
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- sartanbiphenyl
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C253/00—Preparation of carboxylic acid nitriles
- C07C253/30—Preparation of carboxylic acid nitriles by reactions not involving the formation of cyano groups
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Abstract
The present invention provides a kind of preparation methods of bromo sartanbiphenyl, comprising: puts into catalyst sodium bromate in a kettle, organic solvent dichloromethane is added in kettle, bromine is added after material dissolution in sartanbiphenyl, carries out bromination reaction；The molar ratio of each component is sartanbiphenyl: bromine: sodium bromate=1:0.4-0.6:0.1-0.3；Layering, collected organic layer, and the organic layer of collection is gone into precipitation crystallization kettle；Get rid of the methylene chloride in organic layer；Toluene progress crystallization is added and obtains bromo sartanbiphenyl.The present invention uses sartanbiphenyl, bromine for raw material using sodium bromate as catalyst, and by further controlling reaction temperature and material proportion, entire reaction conversion ratio can be made effectively to be increased to 92.1%, and process stabilizing.
Description
Technical field
The present invention relates to substance synthesis technical field more particularly to a kind of preparation methods of bromo sartanbiphenyl.
Background technique
2- cyano -4'- bromomethylbiphenyl (i.e. bromo sartanbiphenyl) is the main intermediate for synthesizing sartans.2- cyanogen
The prior synthesizing method of base -4'- bromomethylbiphenyl mainly has: NBS bromination method and bromine bromination method.NBS bromination method there is also with
Lower deficiency: (1) need to usually use carbon tetrachloride, dichloroethanes as solvent, and carbon tetrachloride, dichloroethanes are in medicine synthesis
A kind of solvent being forbidden to use is not suitable for production and needs；(2) usually using AIBN or BPO as initiator, reaction mechanism is similar
Technology stability is bad in radical reaction, amplification production process, poor controllability；(3) raw materials for production cost is relatively high.Bromine
Bromination method needs catalyst due to using bromine in production, and used catalyst mainly has: cuprous bromide, triphenyl
Phosphine rate nickel, zinc chloride etc., but it is not high using these catalyst efficiency, lead to the receipts of 2- cyano -4'- bromomethylbiphenyl
Rate is lower.
Summary of the invention
The purpose of the present invention is to overcome the defects in the prior art, provides a kind of preparation side of bromo sartanbiphenyl
Method, the catalyst using sodium bromate as bromo-reaction can make entire reaction conversion ratio effectively be increased to 92.1%, and
And process stabilizing.
The present invention is implemented as follows:
The present invention provides a kind of preparation methods of bromo sartanbiphenyl comprising following steps:
Step 1 puts into catalyst sodium bromate in a kettle, and organic solvent dichloromethane is added in kettle, sartanbiphenyl,
After material dissolution, bromine is added, carries out bromination reaction；The molar ratio of each component is sartanbiphenyl: bromine: sodium bromate
=1:0.4-0.6:0.1-0.3；The reaction route is as follows:
Step 2, layering, collected organic layer, and the organic layer of collection is gone into precipitation crystallization kettle；
Step 3 gets rid of organic solvent dichloromethane in organic layer；
Step 4, addition toluene carry out crystallization and obtain bromo sartanbiphenyl.
Preferably, concrete operations are to be directly placed into water in a kettle in the step 1, stir lower investment sodium bromate, so
Methylene chloride is added afterwards in kettle, after adding well, adds sartanbiphenyl in kettle, after material dissolution, bromine is added.
Preferably, in the step 1, the bromination reaction temperature is controlled at 38-45 DEG C, then controls temperature in 38-45
DEG C heat preservation 4-6 hours.
Preferably, the concrete operations in the step 2 are, stratification temperature control is at 25-35 DEG C, collected organic layer, water layer
Barrelling recycling adds water and anhydrous sodium sulfite mixed solution to wash organic layer twice, then is layered collected organic layer；Add water washing
Once, the organic layer of collection is gone into precipitation crystallization kettle, stratification, collected organic layer.
Preferably, the concrete operations in the step 3 are to open stirring, in precipitation crystallization kettle controlled at 40-50
DEG C, first air-distillation removes methylene chloride, is evaporated under reduced pressure again until temperature is 50 DEG C to dry.
Preferably, the concrete operations in the step 4 are that toluene is put into the precipitation crystallization kettle, and stirring is opened and steamed
Vapour is warming up to 60-65 DEG C, after material dissolved clarification, cools between 0-5 DEG C after keeping the temperature half an hour, keeps the temperature 1 hour crystallization, heat preservation knot
Shu Jinhang centrifugation, until terminal to liquid outlet goes out without continuous filtering liquid stream substantially.
The invention has the advantages that:
The present invention uses sartanbiphenyl, bromine for raw material using sodium bromate as catalyst, and passes through further control reaction
Temperature and material proportion not but not reduce reaction yield, instead reaction yield are greatly improved；Meanwhile so that ginseng
Less with the side reaction reacted, the impurity in products obtained from is less.Yield and the higher bromo sartanbiphenyl of purity are obtained,
Entire reaction conversion ratio can be made effectively to be increased to 92.1%, and process stabilizing.
Specific embodiment
Embodiment 1
1, it is directly placed into water in a kettle, opens stirring investment 0.1mo l sodium bromate, dichloromethane then is added from measuring tank
Alkane after adding well, adds 1mo l sartanbiphenyl in kettle in kettle.After material dissolution, bromine 0.4mo l is added, control temperature exists
38-45 DEG C of micro- reflux.Control temperature 38-45 DEG C heat preservation 4-6 hours, heat preservation terminates.Layering, collected organic layer, water layer barrelling
Then recycling adds water and anhydrous sodium sulfite mixed solution to wash twice respectively.Layering, collected organic layer, water layer are discharged into waste water
System.Then adding water washed once, and the organic layer of collection is gone to precipitation crystallization kettle.It stands, layering, collected organic layer, water
Layer is discharged into waste water system.Stratification temperature is controlled at 25-35 DEG C.Stirring is opened in precipitation crystallization kettle, controls interior 40-50 DEG C of temperature, first
Toluene in gravity tank is put into precipitation kettle by air-distillation methylene chloride until being evaporated under reduced pressure again after 50 DEG C to doing.Stirring is opened,
It opens steam and is warming up to 60-65 DEG C, after material dissolved clarification, cooled between 0-5 DEG C after keeping the temperature half an hour, keep the temperature 1 hour crystallization.It protects
Temperature terminates to be centrifuged, until terminal to liquid outlet goes out without continuous filtering liquid stream substantially.The molar ratio of each component is Sha Tanlian
Benzene: bromine: sodium bromate=1:0.4:0.1；
2, the bromo sartanbiphenyl finally obtained, molar yield 90.7%, HPLC purity are 98.4%.
Embodiment 2
1, it is directly placed into water in a kettle, opens stirring investment 0.3mo l sodium bromate, dichloromethane then is added from measuring tank
Alkane after adding well, adds 1mo l sartanbiphenyl in kettle in kettle.After material dissolution, 0.6mo l bromine is added, control temperature exists
38-45 DEG C of micro- reflux.Control temperature 38-45 DEG C heat preservation 4-6 hours, heat preservation terminates.Layering, collected organic layer, water layer barrelling
Then recycling adds water and anhydrous sodium sulfite mixed solution to wash twice respectively.Layering, collected organic layer, water layer are discharged into waste water
System.Then adding water washed once, and the organic layer of collection is gone to precipitation crystallization kettle.It stands, layering, collected organic layer, water
Layer is discharged into waste water system.Stratification temperature is controlled at 25-35 DEG C.Stirring is opened in precipitation crystallization kettle, controls interior 40-50 DEG C of temperature, first
Toluene in gravity tank is put into precipitation kettle by air-distillation methylene chloride until being evaporated under reduced pressure again after 50 DEG C to doing.Stirring is opened,
It opens steam and is warming up to 60-65 DEG C, after material dissolved clarification, cooled between 0-5 DEG C after keeping the temperature half an hour, keep the temperature 1 hour crystallization.It protects
Temperature terminates to be centrifuged, until terminal to liquid outlet goes out without continuous filtering liquid stream substantially.The molar ratio of each component is Sha Tanlian
Benzene: bromine: sodium bromate=1:0.6:0.3；
2, the bromo sartanbiphenyl finally obtained, molar yield 91.5%, HPLC purity are 98.8%.
Embodiment 3
1, it is directly placed into water in a kettle, opens stirring investment 0.2mo l sodium bromate, dichloromethane then is added from measuring tank
Alkane after adding well, adds 1mo l sartanbiphenyl in kettle in kettle.After material dissolution, 0.5mo l bromine is added, control temperature exists
38-45 DEG C of micro- reflux.Control temperature 38-45 DEG C heat preservation 4-6 hours, heat preservation terminates.Layering, collected organic layer, water layer barrelling
Then recycling adds water and anhydrous sodium sulfite mixed solution to wash twice respectively.Layering, collected organic layer, water layer are discharged into waste water
System.Then adding water washed once, and the organic layer of collection is gone to precipitation crystallization kettle.It stands, layering, collected organic layer, water
Layer is discharged into waste water system.Stratification temperature is controlled at 25-35 DEG C.Stirring is opened in precipitation crystallization kettle, controls interior 40-50 DEG C of temperature, first
Toluene in gravity tank is put into precipitation kettle by air-distillation methylene chloride until being evaporated under reduced pressure again after 50 DEG C to doing.Stirring is opened,
It opens steam and is warming up to 60-65 DEG C, after material dissolved clarification, cooled between 0-5 DEG C after keeping the temperature half an hour, keep the temperature 1 hour crystallization.It protects
Temperature terminates to be centrifuged, until terminal to liquid outlet goes out without continuous filtering liquid stream substantially.The molar ratio of each component is Sha Tanlian
Benzene: bromine: sodium bromate=1:0.5:0.2；
2, the bromo sartanbiphenyl finally obtained, molar yield are that 91.8%HPLC purity is 98.6%.
Embodiment 4
1, it is directly placed into water in a kettle, opens stirring investment 0.19mo l sodium bromate, dichloro then is added from measuring tank
Methane after adding well, adds 1mo l sartanbiphenyl in kettle in kettle.After material dissolution, 0.51mo l bromine, control temperature is added
Degree is in 38-45 DEG C of micro- reflux.Control temperature 38-45 DEG C heat preservation 4-6 hours, heat preservation terminates.Layering, collected organic layer, water layer
Barrelling recycling, then adds water and anhydrous sodium sulfite mixed solution to wash twice respectively.Layering, collected organic layer, water layer are discharged into
Waste water system.Then adding water washed once, and the organic layer of collection is gone to precipitation crystallization kettle.It stands, layering is collected organic
Layer, water layer are discharged into waste water system.Stratification temperature is controlled at 25-35 DEG C.Stirring is opened in precipitation crystallization kettle, controls interior temperature 40-50
DEG C, the toluene in gravity tank is put into precipitation kettle by first air-distillation methylene chloride until being evaporated under reduced pressure again after 50 DEG C to doing.It opens
Stirring, opens steam and is warming up to 60-65 DEG C, after material dissolved clarification, cools between 0-5 DEG C after keeping the temperature half an hour, keeps the temperature 1 hour and analyse
It is brilliant.Heat preservation terminates to be centrifuged, until terminal to liquid outlet goes out without continuous filtering liquid stream substantially.The molar ratio of each component is,
Sartanbiphenyl: bromine: sodium bromate=1:0.51:0.19；
2, the bromo sartanbiphenyl finally obtained, molar yield 92.1%, HPLC purity are 99.8%.
Comparative example 1
In addition to replacing sodium bromate with conventional catalyst cuprous bromide, remaining condition is the same as embodiment 4.
The bromo sartanbiphenyl finally obtained, molar yield 71.2%, HPLC purity are 71.6%.
Through the foregoing embodiment and comparative example, it can be seen that the present invention is using sodium bromate as catalyst, using Sha Tanlian
Benzene, bromine are raw material, and by further controlling reaction temperature and material proportion, not but not reduce reaction yield, make instead
Reaction yield is obtained to be greatly improved；Meanwhile so that the side reaction for participating in reaction is less, the impurity in products obtained from is less.
Yield and the higher bromo sartanbiphenyl of purity are obtained, entire reaction conversion ratio can be made effectively to be increased to 92.1%, and
And process stabilizing.
The foregoing is merely illustrative of the preferred embodiments of the present invention, is not intended to limit the invention, all in essence of the invention
Within mind and principle, any modification, equivalent replacement, improvement and so on be should all be included in the protection scope of the present invention.
Claims (6)
1. a kind of preparation method of bromo sartanbiphenyl, which is characterized in that it includes the following steps:
Step 1 puts into catalyst sodium bromate in a kettle, organic solvent dichloromethane is added in kettle, sartanbiphenyl, to object
After material dissolution, bromine is added, carries out bromination reaction；The molar ratio of each component is sartanbiphenyl: bromine: sodium bromate=1:
0.4-0.6:0.1-0.3；
Step 2, layering, collected organic layer, and the organic layer of collection is gone into precipitation crystallization kettle；
Step 3 gets rid of organic solvent dichloromethane in organic layer；
Step 4, addition toluene carry out crystallization and obtain bromo sartanbiphenyl.
2. the preparation method of bromo sartanbiphenyl as described in claim 1, which is characterized in that concrete operations in the step 1
To be directly placed into water in a kettle, stirring lower investment sodium bromate, methylene chloride is then added in kettle, after adding well, gaza is smooth
Biphenyl is in kettle, and after material dissolution, bromine is added.
3. the preparation method of bromo sartanbiphenyl as described in claim 1, which is characterized in that in the step 1, described in control
Bromination reaction temperature at 38-45 DEG C, then control temperature 38-45 DEG C heat preservation 4-6 hours.
4. the preparation method of bromo sartanbiphenyl as described in claim 1, which is characterized in that the specific behaviour in the step 2
As at 25-35 DEG C, collected organic layer, water layer barrelling recycling adds water and anhydrous sodium sulfite mixed solution for stratification temperature control
It washs organic layer twice, then is layered collected organic layer；Adding water washed once, and the organic layer of collection is gone to precipitation crystallization kettle,
Stratification, collected organic layer.
5. the preparation method of bromo sartanbiphenyl as described in claim 1, which is characterized in that the specific behaviour in the step 3
As, stirring is opened in precipitation crystallization kettle, controlled at 40-50 DEG C, first air-distillation removal methylene chloride, until temperature is 50
It DEG C is evaporated under reduced pressure again to dry.
6. the preparation method of bromo sartanbiphenyl as described in claim 1, which is characterized in that the specific behaviour in the step 4
As, toluene is put into the precipitation crystallization kettle, is stirred, steam is opened and is warming up to 60-65 DEG C, after material dissolved clarification, heat preservation
It is cooled between 0-5 DEG C after half an hour, keeps the temperature 1 hour crystallization, heat preservation terminates to be centrifuged, and terminal to liquid outlet is substantially without continuous
Until filtrate is flowed out.
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| CN201810813436.0A CN108947870B (en) | 2018-07-23 | 2018-07-23 | Preparation method of bromosartanbiphenyl |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112441942A (en) * | 2020-12-24 | 2021-03-05 | 江苏新瑞药业有限公司 | Debromination method of sartans intermediate polybrominated substituent |
| CN114426501A (en) * | 2021-12-23 | 2022-05-03 | 山东艾孚特科技有限公司 | Preparation method of bromosartanbiphenyl based on aqueous phase reaction |
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| US6111114A (en) * | 1997-04-11 | 2000-08-29 | Istituto Luso Farmaco D'italia S.P.A. | Process for the preparation of 4-bromomethyl diphenyl compounds |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112441942A (en) * | 2020-12-24 | 2021-03-05 | 江苏新瑞药业有限公司 | Debromination method of sartans intermediate polybrominated substituent |
| CN112441942B (en) * | 2020-12-24 | 2024-03-26 | 江苏新瑞药业有限公司 | Debromination method of sartan intermediate polybrominated substituent |
| CN114426501A (en) * | 2021-12-23 | 2022-05-03 | 山东艾孚特科技有限公司 | Preparation method of bromosartanbiphenyl based on aqueous phase reaction |
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