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What is a simple way to convert an ester into carboxylic acid?
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Ahtashamali Siddiqui
What is a simple way to convert an ester into carboxylic acid?
Alkaline medium is the best way to convert esters into carboxylic acid. if your ester is soluble in Methanol, use Methanol/KOH. it is fast and easy to purify. if not soluble in Methanol, choose another water soluble solvent. note that water is important in the reaction process.
Alkaline medium is the best way to convert esters into carboxylic acid. if your ester is soluble in Methanol, use Methanol/KOH. it is fast and easy to purify. if not soluble in Methanol, choose another water soluble solvent. note that water is important in the reaction process.
dissolve ester (1 eq) in sufficient methanol, then add slowly LiOH (2.0eq) aqueous solution (in equal volume that methanol), at this point you form lithium salt. Follow by TLC, the product is more polar than ester.
second step:
evaporate metanol/water and then add water to dissolve salt. You can protonate with NH4Cl or HCl and extract with ethyl acetate.
dissolve ester (1 eq) in sufficient methanol, then add slowly LiOH (2.0eq) aqueous solution (in equal volume that methanol), at this point you form lithium salt. Follow by TLC, the product is more polar than ester.
second step:
evaporate metanol/water and then add water to dissolve salt. You can protonate with NH4Cl or HCl and extract with ethyl acetate.
You can do it with KOH-methanol In a typical experiment: To a stirring solution of ester (1gm) and methanol (5 mL), KOH (2 molar equiv) was added at 35C. The reaction was allowed to continue for 1 hr then quenched by addition of water (20 mL). ---the unreacted ester (if any) was removed by ether extration and the aqueous layer was acidified. The resulting acid either precipitated out and collected by filtration or extracted from the aqueous layer by organic solvent (e.g. ether, ethyl acetate, methylene chloride...).
You can do it with KOH-methanol In a typical experiment: To a stirring solution of ester (1gm) and methanol (5 mL), KOH (2 molar equiv) was added at 35C. The reaction was allowed to continue for 1 hr then quenched by addition of water (20 mL). ---the unreacted ester (if any) was removed by ether extration and the aqueous layer was acidified. The resulting acid either precipitated out and collected by filtration or extracted from the aqueous layer by organic solvent (e.g. ether, ethyl acetate, methylene chloride...).
Most of the way to convert ester to acid by alkaline hydrolysis but some ester workout fast and clean reaction with acid hydrolysis like HCl water HBr water etc, may be some times Levi's acid also wok for that target
Most of the way to convert ester to acid by alkaline hydrolysis but some ester workout fast and clean reaction with acid hydrolysis like HCl water HBr water etc, may be some times Levi's acid also wok for that target
Dissolved the ester in ethanol or methanol as solvent and add 3 eq sodium hydroxide as base , heated the solution at reflux for 1 hr. Check the TLC for complete conversion .After complete conversion remove the solvent under reduced pressure , in remaining reaction mixture add 1M HCl dropwise precipitate acid product .
Dissolved the ester in ethanol or methanol as solvent and add 3 eq sodium hydroxide as base , heated the solution at reflux for 1 hr. Check the TLC for complete conversion .After complete conversion remove the solvent under reduced pressure , in remaining reaction mixture add 1M HCl dropwise precipitate acid product .
Well, some ester, we experienced the difficulty in all the above methods. I have a 4 ester group in our compound and all four has to be converted to acid, any other solutions? Thanks.
Well, some ester, we experienced the difficulty in all the above methods. I have a 4 ester group in our compound and all four has to be converted to acid, any other solutions? Thanks.
Simple way to convert an ester into carboxylic acid by hydrolysis of ester with aqueous NaOH and then neutralizing the resulting reaction mixture with aq.HCl .
Simple way to convert an ester into carboxylic acid by hydrolysis of ester with aqueous NaOH and then neutralizing the resulting reaction mixture with aq.HCl .
Depending on the nature of the ester group, we can select acidic or alkaline medium for the conversion of ester to acid. 1. using acidic reflux with dilute HCl/H2SO4 resulted in the formation of acid (you have to used very dilute acid to prevent reverse reaction) 2. The other way is already discussed earlier by so many researchers. The ester is reflux in alcohol with a dilute first group alkali like sodium/potassium/Lithium hydroxide solution. this is more better one than earlier because reactions are irreversible and easy to separate. The formed alcohol is basically high volatile compound so it can be distilled off easily by increasing the temperature. by doing so resulted with sodium/potassium/Lithium salt of acid. Then do the work up with slightly strong acid repeat until the pH of the solution become above 12 resulted desired acid as product.
Depending on the nature of the ester group, we can select acidic or alkaline medium for the conversion of ester to acid. 1. using acidic reflux with dilute HCl/H2SO4 resulted in the formation of acid (you have to used very dilute acid to prevent reverse reaction) 2. The other way is already discussed earlier by so many researchers. The ester is reflux in alcohol with a dilute first group alkali like sodium/potassium/Lithium hydroxide solution. this is more better one than earlier because reactions are irreversible and easy to separate. The formed alcohol is basically high volatile compound so it can be distilled off easily by increasing the temperature. by doing so resulted with sodium/potassium/Lithium salt of acid. Then do the work up with slightly strong acid repeat until the pH of the solution become above 12 resulted desired acid as product.
the suspension of ester and LiOH stirred in THF: water (2:1) for 2 h, then we will get lithium salt of acid, it was neutralized by dil HCl you will get corresponding carboxylic acid.
the suspension of ester and LiOH stirred in THF: water (2:1) for 2 h, then we will get lithium salt of acid, it was neutralized by dil HCl you will get corresponding carboxylic acid.
Alkaline medium is the best way to convert esters into carboxylic acid. if your ester is soluble in Methanol, use Methanol/KOH. it is fast and easy to purify. if not soluble in Methanol, choose another water soluble solvent. note that water is important in the reaction process.
Alkaline medium is the best way to convert esters into carboxylic acid. if your ester is soluble in Methanol, use Methanol/KOH. it is fast and easy to purify. if not soluble in Methanol, choose another water soluble solvent. note that water is important in the reaction process.
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first step:
dissolve ester (1 eq) in sufficient methanol, then add slowly LiOH (2.0eq) aqueous solution (in equal volume that methanol), at this point you form lithium salt. Follow by TLC, the product is more polar than ester.
second step:
evaporate metanol/water and then add water to dissolve salt. You can protonate with NH4Cl or HCl and extract with ethyl acetate.
good luck!
first step:
dissolve ester (1 eq) in sufficient methanol, then add slowly LiOH (2.0eq) aqueous solution (in equal volume that methanol), at this point you form lithium salt. Follow by TLC, the product is more polar than ester.
second step:
evaporate metanol/water and then add water to dissolve salt. You can protonate with NH4Cl or HCl and extract with ethyl acetate.
good luck!
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You can do it with KOH-methanol
In a typical experiment: To a stirring solution of ester (1gm) and methanol (5 mL), KOH (2 molar equiv) was added at 35C. The reaction was allowed to continue for 1 hr then quenched by addition of water (20 mL).
---the unreacted ester (if any) was removed by ether extration and the aqueous layer was acidified. The resulting acid either precipitated out and collected by filtration or extracted from the aqueous layer by organic solvent (e.g. ether, ethyl acetate, methylene chloride...).
Good luck
You can do it with KOH-methanol
In a typical experiment: To a stirring solution of ester (1gm) and methanol (5 mL), KOH (2 molar equiv) was added at 35C. The reaction was allowed to continue for 1 hr then quenched by addition of water (20 mL).
---the unreacted ester (if any) was removed by ether extration and the aqueous layer was acidified. The resulting acid either precipitated out and collected by filtration or extracted from the aqueous layer by organic solvent (e.g. ether, ethyl acetate, methylene chloride...).
Good luck
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VOTE
Most of the way to convert ester to acid by alkaline hydrolysis but some ester workout fast and clean reaction with acid hydrolysis like HCl water HBr water etc, may be some times Levi's acid also wok for that target
Most of the way to convert ester to acid by alkaline hydrolysis but some ester workout fast and clean reaction with acid hydrolysis like HCl water HBr water etc, may be some times Levi's acid also wok for that target
More
VOTE
Dissolved the ester in ethanol or methanol as solvent and add 3 eq sodium hydroxide as base , heated the solution at reflux for 1 hr. Check the TLC for complete conversion .After complete conversion remove the solvent under reduced pressure , in remaining reaction mixture add 1M HCl dropwise precipitate acid product .
Dissolved the ester in ethanol or methanol as solvent and add 3 eq sodium hydroxide as base , heated the solution at reflux for 1 hr. Check the TLC for complete conversion .After complete conversion remove the solvent under reduced pressure , in remaining reaction mixture add 1M HCl dropwise precipitate acid product .
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Use 1M NaOH in a mixed solvent of THF/H2O
Use 1M NaOH in a mixed solvent of THF/H2O
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Use LiOH in methanol followed by rota vapour evaporation of MeOH, then add dilute HCl in water and then work up using water abd DCM..
Use LiOH in methanol followed by rota vapour evaporation of MeOH, then add dilute HCl in water and then work up using water abd DCM..
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Well, some ester, we experienced the difficulty in all the above methods. I have a 4 ester group in our compound and all four has to be converted to acid, any other solutions?
Thanks.
Well, some ester, we experienced the difficulty in all the above methods. I have a 4 ester group in our compound and all four has to be converted to acid, any other solutions?
Thanks.
More
VOTE
Simple way to convert an ester into carboxylic acid by hydrolysis of ester with aqueous NaOH and then neutralizing the resulting reaction mixture with aq.HCl .
Simple way to convert an ester into carboxylic acid by hydrolysis of ester with aqueous NaOH and then neutralizing the resulting reaction mixture with aq.HCl .
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The usual procedure is to dissolve the ester 1Eq in MeOH or EtOH add 4Eq of 1M NaOH and stir for 4-5h.
Sometimes it might be necessary to use a mixture of solvents like MeOH/THF or MeOH/dioxane
Workup: evaporation, add EtOAc and 1M HCl and perform the extraction
The usual procedure is to dissolve the ester 1Eq in MeOH or EtOH add 4Eq of 1M NaOH and stir for 4-5h.
Sometimes it might be necessary to use a mixture of solvents like MeOH/THF or MeOH/dioxane
Workup: evaporation, add EtOAc and 1M HCl and perform the extraction
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Depending on the nature of the ester group, we can select acidic or alkaline medium for the conversion of ester to acid.
1. using acidic reflux with dilute HCl/H2SO4 resulted in the formation of acid (you have to used very dilute acid to prevent reverse reaction)
2. The other way is already discussed earlier by so many researchers. The ester is reflux in alcohol with a dilute first group alkali like sodium/potassium/Lithium hydroxide solution. this is more better one than earlier because reactions are irreversible and easy to separate. The formed alcohol is basically high volatile compound so it can be distilled off easily by increasing the temperature. by doing so resulted with sodium/potassium/Lithium salt of acid. Then do the work up with slightly strong acid repeat until the pH of the solution become above 12 resulted desired acid as product.
Depending on the nature of the ester group, we can select acidic or alkaline medium for the conversion of ester to acid.
1. using acidic reflux with dilute HCl/H2SO4 resulted in the formation of acid (you have to used very dilute acid to prevent reverse reaction)
2. The other way is already discussed earlier by so many researchers. The ester is reflux in alcohol with a dilute first group alkali like sodium/potassium/Lithium hydroxide solution. this is more better one than earlier because reactions are irreversible and easy to separate. The formed alcohol is basically high volatile compound so it can be distilled off easily by increasing the temperature. by doing so resulted with sodium/potassium/Lithium salt of acid. Then do the work up with slightly strong acid repeat until the pH of the solution become above 12 resulted desired acid as product.
More
VOTE
the suspension of ester and LiOH stirred in THF: water (2:1) for 2 h, then we will get lithium salt of acid, it was neutralized by dil HCl you will get corresponding carboxylic acid.
the suspension of ester and LiOH stirred in THF: water (2:1) for 2 h, then we will get lithium salt of acid, it was neutralized by dil HCl you will get corresponding carboxylic acid.
More
VOTE