OChem Tosylation Reaction: Predicting Major Product with p-TsOH Catalyst

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The discussion focuses on predicting the major product of a tosylation reaction involving a compound with both a carboxylic acid and an alcohol group, using p-TsOH as a catalyst. Participants debate whether the tosyl acid will replace the hydroxyl group of the carboxylic acid, the standalone alcohol, or both. It is concluded that the hydroxyl group of the carboxylic acid is part of that functional group and should not be treated as a separate alcohol. The consensus is that the tosylation will likely occur at the secondary alcohol rather than the carboxylic acid. This clarification helps participants feel more confident in their understanding of the reaction dynamics.
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Homework Statement



Predict the major product in the following reaction (Hint: Consider intra-molecular reaction)

Homework Equations



HO2C-(CH2)3-CH(OH)-CH3 ------------cat. p-TsOH, heat----------> ?

The Attempt at a Solution



Essentially what I cannot figure out is if the tosic acid is going to replace the -OH group of the carboxylic acid, the other standalone -OH group, or both. I would assume that it would only replace one since the molecule would likely be more stable, and for that same reason I would also assume that it would replace the 2 prime -OH rather than the -OH attached to the carboxylic acid group.
 
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Adsit_Deus said:

Homework Statement



Predict the major product in the following reaction (Hint: Consider intra-molecular reaction)

Homework Equations



HO2C-(CH2)3-CH(OH)-CH3 ------------cat. p-TsOH, heat----------> ?

The Attempt at a Solution



Essentially what I cannot figure out is if the tosic acid is going to replace the -OH group of the carboxylic acid, the other standalone -OH group, or both. I would assume that it would only replace one since the molecule would likely be more stable, and for that same reason I would also assume that it would replace the 2 prime -OH rather than the -OH attached to the carboxylic acid group.
A screenshot of the molecule in Marvin Sketch is attached
 

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Adsit_Deus said:
and for that same reason I would also assume that it would replace the 2 prime -OH rather than the -OH attached to the carboxylic acid group.
And, your doubts regarding your assumption are what?
 
My original thought was stability, but I am not sure. We were never shown an example problem where there was any more than one -OH group in class, nor were we shown what could happen if there are two oxygen-centric functional groups. I just do not know how to go about dealing with them since we only worked one or two problems with run-of-the-mill 1 and 2 prime alcohols.
 
The second "-OH" group you're worried about doesn't work as such; it's part of the carboxylic acid functional group and has to be treated as being part of that group rather as another alcohol group. Feel a little more comfortable?
 
Extremely, thank you. I was mainly unsure of that exact point. "Is is still treated as a lone hydroxyl group, or is it treated as a part of a group that does not necessarily obey that tosylate rule?" That clears everything up.
 
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