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What structure of carboxylic acids gives the highest acidity?
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+ Carboxylic acids
+ Physical chemistry
+ Molecular structure
+ Physical organic chemistry
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Mike Webster
What structure of carboxylic acids gives the highest acidity?
Are you examining us, Sir? ;) The highest acidity in this case is when X donates electrons the least. As far as I remember organic chemistry, it is vinyl. Wrong?
Are you examining us, Sir? ;) The highest acidity in this case is when X donates electrons the least. As far as I remember organic chemistry, it is vinyl. Wrong?
α,β-unsaturated acids as D. Bloch suggested are more acidic than the saturated ones with the same chain length. Moreover cis is more acidic than trans in this case. But I think even the shortest one is not as acidic as simple formic acid. By the way there are a lot of tables with pka-values available in the internet.
α,β-unsaturated acids as D. Bloch suggested are more acidic than the saturated ones with the same chain length. Moreover cis is more acidic than trans in this case. But I think even the shortest one is not as acidic as simple formic acid. By the way there are a lot of tables with pka-values available in the internet.
Thank you very much. Yes, I fully agree with you. However, if you exclude Si you only have vinyl groups. Then, this is known indeed. The effect is not large and I'd like to know if somethinsg significantly stronger has been reported.
Thank you very much. Yes, I fully agree with you. However, if you exclude Si you only have vinyl groups. Then, this is known indeed. The effect is not large and I'd like to know if somethinsg significantly stronger has been reported.
Well, of course, CF3 strongly increases acidities and oxalate anion is chelated. In other cases there is a competition between polarizability and other effects.
Indicators are useful&valuable. However one has to have a compound to study with the indicator and this is my question.
In short, what I am looking for is the strongest of a family of weak acids with the rules of the game I indicated.. I found very few experimental results and got tired of systematic explorations.
Well, of course, CF3 strongly increases acidities and oxalate anion is chelated. In other cases there is a competition between polarizability and other effects.
Indicators are useful&valuable. However one has to have a compound to study with the indicator and this is my question.
In short, what I am looking for is the strongest of a family of weak acids with the rules of the game I indicated.. I found very few experimental results and got tired of systematic explorations.
Are you examining us, Sir? ;) The highest acidity in this case is when X donates electrons the least. As far as I remember organic chemistry, it is vinyl. Wrong?
Are you examining us, Sir? ;) The highest acidity in this case is when X donates electrons the least. As far as I remember organic chemistry, it is vinyl. Wrong?
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α,β-unsaturated acids as D. Bloch suggested are more acidic than the saturated ones with the same chain length. Moreover cis is more acidic than trans in this case. But I think even the shortest one is not as acidic as simple formic acid. By the way there are a lot of tables with pka-values available in the internet.
α,β-unsaturated acids as D. Bloch suggested are more acidic than the saturated ones with the same chain length. Moreover cis is more acidic than trans in this case. But I think even the shortest one is not as acidic as simple formic acid. By the way there are a lot of tables with pka-values available in the internet.
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You can compare their acidity by adding a suitable color indicator (anilines family) then measure the UV-Vis absorbance.
You can compare their acidity by adding a suitable color indicator (anilines family) then measure the UV-Vis absorbance.
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Thank you very much. Yes, I fully agree with you. However, if you exclude Si you only have vinyl groups. Then, this is known indeed. The effect is not large and I'd like to know if somethinsg significantly stronger has been reported.
JL
Thank you very much. Yes, I fully agree with you. However, if you exclude Si you only have vinyl groups. Then, this is known indeed. The effect is not large and I'd like to know if somethinsg significantly stronger has been reported.
JL
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Very kind of you. Yes, I have been searching but I fail to find some really important effects. Thank you very much.
JL
Very kind of you. Yes, I have been searching but I fail to find some really important effects. Thank you very much.
JL
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No, I think for a significant effect you need electron withdrawing groups like CF3 which generally contain hetero atoms.
I do not know if dicarboxylic acids fit into your demand, but oxalic acid is very acidic.
No, I think for a significant effect you need electron withdrawing groups like CF3 which generally contain hetero atoms.
I do not know if dicarboxylic acids fit into your demand, but oxalic acid is very acidic.
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Thank you so much for these answers.
Well, of course, CF3 strongly increases acidities and oxalate anion is chelated. In other cases there is a competition between polarizability and other effects.
Indicators are useful&valuable. However one has to have a compound to study with the indicator and this is my question.
In short, what I am looking for is the strongest of a family of weak acids with the rules of the game I indicated.. I found very few experimental results and got tired of systematic explorations.
Thank you so much for these answers.
Well, of course, CF3 strongly increases acidities and oxalate anion is chelated. In other cases there is a competition between polarizability and other effects.
Indicators are useful&valuable. However one has to have a compound to study with the indicator and this is my question.
In short, what I am looking for is the strongest of a family of weak acids with the rules of the game I indicated.. I found very few experimental results and got tired of systematic explorations.
More
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