Sythesis of isopentyl acetate report questions

  • Thread starter Thread starter osumc2014
  • Start date Start date
  • Tags Tags
    Report
Click For Summary

Discussion Overview

The discussion revolves around the synthesis of isopentyl acetate through the Fischer esterification of isopentyl alcohol and acetic acid. Participants raise questions regarding the presence of unreacted alcohols, factors affecting yield, and methods to improve the yield, including the role of various reagents and techniques used during the process.

Discussion Character

  • Technical explanation
  • Debate/contested
  • Experimental/applied

Main Points Raised

  • One participant questions how to confirm the absence of alcohols in the final solution.
  • Another participant suggests that low yield could be attributed to several factors, including time, temperature, catalyst efficiency, and extraction techniques.
  • Improving yield may involve sequestering one of the products as it forms, with a reference to the Dean-Stark apparatus.
  • There is a discussion about the role of sodium bicarbonate in the workup process, with some participants suggesting it helps reduce acidity after esterification.
  • Clarification is made regarding the solubility of isopentyl alcohol compared to isopropyl alcohol, affecting extraction methods.
  • A participant asks about the purpose of refluxing in the reaction process.
  • One participant reports a specific yield of 38.13% and questions potential causes for the discrepancy in expected versus actual product mass.

Areas of Agreement / Disagreement

Participants express various viewpoints on the factors affecting yield and the role of different reagents, indicating that multiple competing views remain. The discussion does not reach a consensus on the best methods for improving yield or confirming the absence of alcohols.

Contextual Notes

Limitations include potential dependencies on specific experimental conditions, such as the purity of reagents and the efficiency of the distillation process, which are not fully resolved in the discussion.

Who May Find This Useful

This discussion may be useful for students and practitioners involved in organic chemistry, particularly those interested in esterification reactions and yield optimization techniques.

osumc2014
Messages
1
Reaction score
0
Couple questions about the fischer esterification of isopentyl alcohol + acetic acid -----> (acid catalyzed) to form isopentyl acetate or banana oil. Refluxed, used sodium bicarb and na2So4, distilled.
1) how do I know that the final solution did not contain any alcohols?

2)What could have caused a low yield?

3)How to improve the yield? Iknow something w Le chatelier's but anything else?

Thanks!
 
Physics news on Phys.org
The hint is in the use of Na2SO4

Sorry: I Mean its in the use of distillation

(Even though getting a completely pure substance from one distillation is unlikely..)
 
Last edited:
1) NO, the hint is in the use of bicarbonate.
2) time, temperature, catalyst, water in reagents, sloppy work, larger glassware than necessary, warm condenser in the distillation, too much Na2SO4, bad Na2SO4, not enough time over the Na2SO4, bad extraction technique (emulsion), it just goes on and ON!
3) Improve the yield by sequestering one of the products as it is formed. (Dean-Stark?)
 
Whoops, this is what I get for late posting ^^

But why does the use of bicarb have its effects? Surely its just to reduce the acidity after the acid catalysed esterification takes place?
 
Last edited:
The first step of the workup is to extract with water or bicarb. Probably water first followed by a bicarb wash to scavenge the acid. Water is the key of course since the alcohol is isopropyl (water-soluble).

Edit: Whoops! Strike that! Isopentyl alcohol not isopropyl. And isopentyl alcohol is not very water soluble. AbedeuS is right about the distillation being important.
 
Last edited:
what purpose does refluxing serve ?please help.
 
yield was 38.13% and the final ester was 6.87g s opposed to 18.01g.. problems like wat could have caused this?
 

Similar threads

Synthesis of Isopentyl Acetate question
  • · Replies 7 ·
Replies
7
Views
36K