Reaction between marquis reagent and ibuprofen?

  • Thread starter Thread starter dckemp1999
  • Start date Start date
  • Tags Tags
    Reaction
AI Thread Summary
The discussion centers on the reaction between Marquis reagent and ibuprofen, specifically questioning the resulting products and the observed color change compared to paracetamol (acetaminophen). The reaction involves formaldehyde and sulfuric acid with ibuprofen, but the exact product remains unclear. It is noted that ibuprofen produces an orange to brown color change, while paracetamol does not, despite both having aromatic structures. The conversation highlights that ibuprofen may be present as a sodium salt in some formulations, which could influence the reaction. Additionally, the complexity of the Marquis reagent's reactions, including potential acylation and polymerization, complicates understanding the outcomes. The discussion seeks insights into why ibuprofen reacts differently than paracetamol, emphasizing the differences in their molecular structures and reactivity.
dckemp1999
Messages
1
Reaction score
0
How did you find PF?: Social media

Hello there good people,

I would like to know what is the product of the reaction between marquis reagent and ibuprofen?

CH2O is Formaldehyde, SO4 is Sulfuric Acid and C13H1802 is ibuprofen

The reaction is CH2O + SO4 + C13H1802 = ??

I was wondering what this equals and why ibuprofen gives a colour change of orange to brown but paracetamol does not when reacting with Marquis?
 
  • Skeptical
Likes hmmm27 and bob012345
Chemistry news on Phys.org
This is a valid question.

FWIW in US name for paracetamol==acetaminophen (Tylenol). I do not know a good answer, the molecules of both pain killers are different. What I can find on a search: Ibuprofen can affect renal function on overdose, acetaminophen damages liver tissues on overdose. There are Marquis color chart results for both, I believe, because for both illegal and legal drugs the Marquis test result has some legal standing.

@TeethWhitener @chemisttree

pinging two members who may know about how the reactions proceed.

Plus formulations of ibuprofen may possibly be the sodium salt. Which affects your question.
 
Last edited:
  • Informative
Likes pinball1970
I’m under the impression that most Marquis reagent products are poorly characterized, since the reaction conditions are pretty harsh. It apparently involves acylation and possibly polymerization/condensation of multiple molecules, and the final color will be determined by the electronic structure of whatever weird highly conjugated molecule is left at the end of the reaction.

That said, it’s not immediately clear to me why, if aromatic substitution is the main mechanism, paracetamol wouldn’t react but ibuprofen would. They both have an aromatic core with para pendant groups that are pretty strongly activating. Maybe someone else has a better answer.
 
  • Like
Likes Borek and jim mcnamara
Thread 'How to make Sodium Chlorate by Electrolysis of salt water?'
I have a power supply for electrolysis of salt water brine, variable 3v to 6v up to 30 amps. Cathode is stainless steel, anode is carbon rods. Carbon rod surface area 42" sq. the Stainless steel cathode should be 21" sq. Salt is pure 100% salt dissolved into distilled water. I have been making saturated salt wrong. Today I learn saturated salt is, dissolve pure salt into 150°f water cool to 100°f pour into the 2 gallon brine tank. I find conflicting information about brine tank...
Engineers slash iridium use in electrolyzer catalyst by 80%, boosting path to affordable green hydrogen https://news.rice.edu/news/2025/engineers-slash-iridium-use-electrolyzer-catalyst-80-boosting-path-affordable-green Ruthenium is also fairly expensive (a year ago it was about $490/ troy oz, but has nearly doubled in price over the past year, now about $910/ troy oz). I tracks prices of Pt, Pd, Ru, Ir and Ru. Of the 5 metals, rhodium (Rh) is the most expensive. A year ago, Rh and Ir...
Back
Top