Which compound will be extracted in organic layer?

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Discussion Overview

The discussion revolves around predicting which compounds will be extracted into the organic layer versus the aqueous layer when using dichloromethane and sodium hydroxide. Participants explore the effects of acid-base reactions on the solubility of various compounds in organic and aqueous solvents.

Discussion Character

  • Exploratory, Technical explanation, Debate/contested, Homework-related

Main Points Raised

  • One participant predicts that compounds (A) and (B) will be extracted into the aqueous layer due to the formation of charged conjugate bases after deprotonation by NaOH.
  • The same participant predicts that compound (C) will be extracted into the organic layer, reasoning that NaOH will neutralize the NH3+ group, resulting in a neutral compound.
  • Another participant agrees with the initial predictions for compounds (A) and (B) but questions the reasoning for compound (C), suggesting that the provided answers indicate it will not be extracted into the organic layer.
  • There is a suggestion that the pre-lab material may not have been proof-read, raising doubts about the accuracy of the answers provided.
  • A later reply seeks confirmation of the reasoning regarding the deprotonation of compounds (A) and (B) and the neutralization of compound (C).

Areas of Agreement / Disagreement

Participants express uncertainty regarding the extraction predictions, particularly for compound (C). There is no consensus on the correctness of the initial reasoning or the provided answers.

Contextual Notes

Participants highlight potential issues with the pre-lab material, suggesting that it may contain errors or lack clarity, which could affect their understanding of the extraction process.

Who May Find This Useful

This discussion may be useful for students studying organic chemistry, particularly those focusing on extraction techniques and acid-base reactions.

vetgirl1990
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I'm having a lot of trouble predicting which compounds would be extracted into which layer (organic vs. aqueous) using acids and bases.

Using the solvents dichloromethane (which would form the organic layer) and sodium hydroxide (would form the aqueous layer along with water), I am asked to predict which of the following compounds would end up being extracted into the organic layer.

My predictions for the attached compounds:
(A) Would be extracted in the AQUEOUS layer.
NaOH would deprotonate the hydrogen (on the OH) from the bezoic acid, leaving a charged conjugate base.
Charged materials stay in the aqueous layer.

(B) Would be extracted in the AQUEOUS layer.
NaOH would deprotonate the hydrogen (on the OH) from the phenol, leaving a charged conjugate base.
Charged materials stay in the aqueous layer.

(C) Would be extracted in the ORGANIC layer.
NaOH attacks the NH3+ group, forming a neutral compound, and anionic dicyclohexane.
The neutral compound that forms would be extracted in the organic layer.

BUT my reasoning seems to be all wrong! The answers state that compounds (A) and (B) will be extracted into the organic layer, but (C) would not be. Why?
 

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A)? Check. B)? Check. C)? Check.
This could be a "re-cycled" pre-lab that hasn't been proof-read --- who knows.
 
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Bystander said:
A)? Check. B)? Check. C)? Check.
This could be a "re-cycled" pre-lab that hasn't been proof-read --- who knows.

Interesting, that's what I was thinking too... so is my reasoning above correct then? Regarding the base being able to deprotonate A and B to form a charged conjugate base; and neutralizing C to form a neutral compound?
 
That's my take.
 
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