Understanding Fructose: The Role of Ketone in Reducing Sugar Reactions

  • Thread starter Thread starter garytse86
  • Start date Start date
  • Tags Tags
    Sugar
AI Thread Summary
Fructose, a reducing sugar, undergoes oxidation during reactions such as the Benedict's test, where it reduces Cu2+ to Cu+. The discussion raises the question of how a ketone group can be oxidized, noting that typically, aldehydes oxidize to carboxylic acids while ketones are generally resistant to oxidation. However, the iodoform reaction is mentioned as a method to confirm the presence of certain ketones and alcohols. It is highlighted that fructose can isomerize to glucose and mannose through an enediol intermediate, which then participates in oxidation reactions. The conversation also briefly touches on the possibility of oxidizing ketones using carbonyl oxides.
garytse86
Messages
311
Reaction score
0
Fructose is a reducing sugar, and the ketone acts as a reducing centre, which reduces Cu2+ --> Cu+. Therefore fructose itself becomes oxidised.

However, how can a ketone group be oxidised?

I thought: aldehyde becomes oxidised to carboxylic acid
ketone: cannot be oxidised.
 
Chemistry news on Phys.org
Try looking up the iodoform reaction.
 
How does that help. I know the iodoform reaction confirms any 2-one, 2-ol, 2-al, ethanol or ethanal. i.e. CH3C=O, but no hydroxide / iodine for reducing sugar test?
 
Well, from what I remember, the ketone is reduced in this case to a carboxlic acid, although not completely sure. Try finding the mechanism, I just don't have the time right now.
 
Yeah, the fructose isomerizes to glucose and mannose via an enediol, which then oxidizes in the standard Benedict's test fashion.

My students happen to be doing that very experiment today.

If you want to oxidize an actual ketone, there's always carbonyl oxides...
 
ok, thank you very much :D
 

Thread 'Humidity of a saturated NaCl solution with anticaking additive'

I want to test a humidity sensor with one or more saturated salt solutions. The table salt that I have on hand contains one of two anticaking agents, calcium silicate or sodium aluminosilicate. Will the presence of either of these additives (or iodine for that matter) significantly affect the equilibrium humidity? I searched and all the how-to-do-it guides did not address this question. One research paper I found reported that at 1.5% w/w calcium silicate increased the deliquescent point by...
View full post »

Similar threads

Cross Cannizzaro and Intramolecular Cannizzaro
Replies
2
Views
5K
Reduction of a ketone using zinc in acetic acid
Replies
5
Views
8K
Organic II Q's - EAS, sulfur as protecting group, fischer esterification
Replies
2
Views
4K
How can I understand a chemical reaction?
Replies
4
Views
3K
Understanding luminol under ultrasound
Replies
2
Views
3K
What will be the product of this organic reaction?
Replies
28
Views
5K
Understanding Selectivity of Reducing Agents in Organic Chemistry
Replies
5
Views
8K
Understanding Reducing Agents: LiAlH4, NaBH4, H2/Nickel
Replies
5
Views
36K
Can the Beta carbons of ketones act as nucleophiles? And one more question.
Replies
3
Views
4K
Electrochemists brain teaser-copper electrolysis
Replies
1
Views
3K

Hot Threads

Recent Insights

Back
Top