Questions tagged [phenols]

Use this tag for questions about phenols, their synthesis, analysis, properties and more. Do not use the 'alcohols' tag for phenols due to the differences between the two classes.

Filter by
Sorted by
Tagged with
6
votes
0answers
616 views

Why does phenol react on oxygen in the Gattermann–Koch reaction?

When discussing the Gattermann–Koch reaction on phenol substrates, it has been said that O-acylation is a problematic competing reaction as in a phenol, there's high electron density on the O atom [...
6
votes
0answers
2k views

Why is o-fluorophenol a stronger acid than p-fluorophenol?

The $\mathrm{p}K_\mathrm{a}$ value of o-fluorophenol is $8.7$, while that of the p-fluorophenol is $9.9$. It's obvious that the inductive effect is more dominant at ortho-position, which results in a ...
4
votes
2answers
5k views

Hyperconjugation in cresol

In cresol both $+I$ effect as well as hyperconjugation work together to determine its acidity. When the methyl group is present in the ortho- and para-position both of them can act upon phenol. ...
9
votes
2answers
11k views

Can phenol be detected with a ceric ammonium nitrate test?

Today, I came across a question which asked name three reagents can be used for identification of phenol. The answer given was: Neutral $\ce{FeCl3}$ $\ce{ NaNO2 +HCl}$ $\ce {(NH4)2[Ce(NO3)...
8
votes
1answer
3k views

Phenol smell from hands

It is a question which I faced when I was in Senior year in high school, I used my hands to handle phenol which has turned pink due to oxidation, I washed my hands with all kind of soaps but smell in ...
0
votes
2answers
2k views

Between 3-chlorophenol and 3-fluorophenol, which one is more acidic?

Between 3-chlorophenol and 3-fluorophenol, which one is more acidic? In this case, I know that both F and Cl are electron-donating groups. Furthermore, I know that F is more electron-donating than ...
1
vote
2answers
303 views

How is rotenone a polyphenol?

How is it a polyphenol if it doesn't have a hydroxyl group? If it isn't which subclass would you put it in, and which functional groups does it contain?
1
vote
0answers
251 views

Why did phenol respond to Brady's reagent?

I was teaching a friend a few basic organic analysis experiments, during which I was showing him, how to get an alcohol, and took a sample of phenol. The neutral $\ce{FeCl3}$ test went fine(which i ...
0
votes
3answers
670 views

Is there an intramolecular hydrogen bond in guaiacol?

Is there a hydrogen bond between the $\ce{H}$ atom of $\ce{-OH}$ group and the $\ce{O}$ atom of the $\ce{-OCH3}$ group in ortho-methoxyphenol? I was told no. But I want to know why.
7
votes
1answer
2k views

Evaluation of a synthesis from aspirin to paracetamol from this Nile Red video

Recently the YouTube chemist Nile Red performed an interesting conversion from aspirin to paracetamol Aspirin to Acetaminophen - Part 1 of 6: Extracting Aspirin from Pills using the following steps: ...
1
vote
1answer
171 views

Can alkyl-substituted phenols be reduced to alkyl-substituted benzenes by zinc dust?

I know that phenol can be reduced to benzene by distilling it with zinc dust. But I want to know if that concept can be expanded. E.g., take chavicol or 4-(prop-2-en-1-yl)phenol; could you still ...
0
votes
2answers
435 views

Organic problem: acidity of benzene substituents

Ortho nitro benzoic acid is more acidic than para benzoic acid since intermolecular H bonding comes into play in the latter compound. But why is that among para nitro phenol and ortho nitro phenol, ...
0
votes
1answer
8k views

Which Phenols give the colours blue, green or violet in the neutral FeCl3 test?

I have read about the neutral FeCl3 test for Phenols, where a positive test is indicated by the colour of the solution which ranges from green to blue to violet. But which specific derivatives of ...
2
votes
1answer
4k views

Is picric acid a very strong acid?

Picric acid has nitro groups in para and ortho positions, so it has great possibility to go for resonance, thus it is supposed to be a very good acid. But a question arises! The $\ce{O}$ of $\ce{-OH}$...
-1
votes
1answer
3k views

What is the functionality(reactive sites) of phenol molecule? [closed]

My class 12 chemistry textbook says that phenol molecule has three reactive sites or it's functionality is three. But I am confused whether it is so or not, because, what I know, phenol has three ...
-1
votes
2answers
27k views

Why o-Nitrophenol is more volatile than p-Nitrophenol? [duplicate]

Why o-Nitrophenol is more steam volatile than p-Nitrophenol?
1
vote
1answer
1k views

Physical properties of phenols

Order of increasing boiling point is p-nitrophenol > m-nitrophenol > o-nitrophenol. The difference between bp of p- and o-nitrophenol is that one form intermolecular hydrogen bonding while other form ...
5
votes
2answers
1k views

Suggestion for a Synthesis of Paracetamol — plausible?

I have seen a number of different plausible syntheses for paracetamol but they suffer from problems such poor regioselectivity of aromatic substitution (usually when nitrating phenol getting a mixture ...
18
votes
4answers
28k views

Acidity order of nitrophenols

As in other posts I have seen and learnt that, if one is given four compounds, namely para-nitrophenol, ortho-nitrophenol, meta-nitrophenol and phenol and is told to arrange them in order of acidity, ...
3
votes
1answer
4k views

Difference between water solubilities of phenol and cyclohexanol?

The solubility of phenol is 83 g/L, while that of cyclohexanol is 36 g/L. Both of them have a hydroxy group, and can form hydrogen bonds with water. Also, the hydrophobic part of phenol, as well as ...
1
vote
1answer
1k views

Reactions of phloroglucinol

Does phloroglucinol respond to the iodoform test? cerric ammonium nitrate test? 2,4-DNP test? I couldn't find any good sources that answer any of these. I thought of this: Tautomerism can "change" ...
2
votes
3answers
35k views

Why is meta-nitrophenol less acidic than para-nitrophenol? [closed]

My professor said while explaining the acidic nature of phenol that meta-nitrophenol is less acidic than para-nitrophenol, and gave the reason that resonance doesn't play on meta, but I didn't get it.
6
votes
1answer
2k views

Nomenclature of benzene derivatives with two functional groups

In several places, I have seen that while naming benzene derivatives, no priority for substituents is followed. For example, I've seen both 2-hydroxyaniline and 2-aminophenol being used. Is there an ...
13
votes
1answer
49k views

What is the product of the chemical reaction between phenol and ferric chloride?

The chemical reaction between phenol and ferric chloride is a test for the presence of phenol. They react with each other to produce a violet complex. However, the reaction is given differently in ...
2
votes
1answer
12k views

Why is phenol more polar than alcohol?

Why is phenol more polar than alcohol. I mean the benzene ring seems to be extremely unpolar. Furthermore, is the hydrogen bonding stronger in phenol than in alcohol? Are polarity and hydrogen bonding ...
7
votes
1answer
2k views

Synthesis of 2-methyl-4-nitrophenol from benzene?

Benzene first reacts with the reagents $\ce{CH3Cl/AlCl3}$, to attach a methyl ($\ce{CH3}$) group to the benzene ring. Then I suggested reacting with $\ce{OH-}$. Because the methyl group is an ...
0
votes
0answers
2k views

What exactly happens at the critical solution temperature of a phenol water system?

What makes phenol that was turbid go clear beyond the critical solution temperature? We say beyond the critical solution temperature the constituents become soluble. What is the reaction or the exact ...
7
votes
1answer
5k views

How does the solvent determine whether mono- or tribromination of phenol occurs?

In phenol, the $-\ce{OH}$ group activates the benzene ring towards electrophilic substitution. But why is it that the electrophilic bromination of phenol gives trisubstitution (forming 2,4,6-...
5
votes
2answers
879 views

How to esterify phenol with oxalic acid?

Is it possible to fully esterify phenol with oxalic acid in order to get diphenyl oxalate? What catalyst should I use and is the synthesis possible to perform at home with hobby equipment?
6
votes
1answer
2k views

Can the hydroxyl group of 4-hydroxybenzoic acid react with phosphorus pentachloride?

I learned that, a phenol will not react (or react very slowly) with $\ce{PCl5}$ due to its stabilized structure. How about the $\ce{-OH}$ group on the benzene ring of 4-hydroxybenzoic acid? Will that ...
2
votes
1answer
5k views

What is the reason for the acidic character in phenols?

I came across this concerning phenols: The hydroxyl group, in phenol is directly attached to the $\ce{sp^2}$ hybridised carbon of benzene ring which acts as an electron withdrawing group. ...
4
votes
1answer
3k views

Activity of different positions in phenol with respect to electrophilic aromatic substitution

Which of the statements below is correct? a) The ortho and para positions are more active than the meta position. or b) The ortho and para positions are activated while the meta position is ...
11
votes
2answers
789 views

Alkylation of 1-naphthol in trifluoroethanol versus in DMSO

I am supposed to work out which product is formed in which solvent when naphthalen-1-olate is treated with benzyl iodide. DMSO is a polar aprotic solvent, as it does not possess an acidic hydrogen. ...
18
votes
5answers
9k views

Strength of hydrogen bonding in phenol or methanol

I wanted to know whether hydrogen bonding is stronger in phenol or methanol. I saw on Wikipedia about the enthalpies of hydrogen bonding in various cases. but could not find the answer to this ...
7
votes
1answer
1k views

Selective alkylation of carboxylic acid versus phenol

Starting from the ketone shown, I plan to use a haloform reaction to transform the acetyl group into a carboxylic acid. Following that, there are two alkylations to be carried out: one esterification ...
13
votes
3answers
47k views

Gattermann-Koch Reaction with Phenol Substrates

The Gattermann-Koch Reaction involves the formation of an aryl aldehyde using carbon monoxide and hydrochloric acid as reactants. The reaction is catalyzed by aluminium trichloride in the presence of ...
13
votes
3answers
32k views

Friedel–Crafts reaction of phenol

Does phenol undergo Friedel–Crafts reactions or does it react with Lewis acids like aniline does?
10
votes
1answer
6k views

Why is picric acid more acidic than carbonic acid?

I just had a question in a test asking to compare the relative acidity of picric acid (TNP) and carbonic acid, $\ce{H2CO3}$ (not phenol). It turns out that TNP is more acidic. I have no idea why? Is ...
8
votes
2answers
3k views

Aromatic ether to phenol reagents

I have been asked to identify suitable reagents for the following transformation: (Apologies it's back to front - the question is a map of reactions and I took a snapshot). I really have no idea ...
13
votes
3answers
18k views

Why is a hydroxyl group more activating than a methoxy group in electrophilic aromatic substitution?

Why is phenol more reactive towards electrophilic substitution than methoxybenzene? Isn't the lone pair on the methoxy group oxygen more available for participating in resonance into the ring than the ...
6
votes
2answers
4k views

How do we know whether we will get a mono substituted or tri-substituted product during electrophilic aromatic substitution?

For example consider the bromination of phenol we get the tri-substituted product (even though bromine is deactivating so I suppose it should deactivate the ring with each addition) while sulphonation ...
9
votes
2answers
10k views

Inductive vs resonance effects and the acidity of phenol

A lot of people rationalize the acidity of phenol by saying that resonance is responsible for much of phenol's acidity as opposed to aliphatic alcohols. However, this image suggests that in fact the ...
6
votes
3answers
7k views

How are phenols made?

What is the equation and conditions for the synthesis of phenols? Would it work if we added $\ce{NaOH}$ to benzene and then refluxed?
33
votes
1answer
51k views

Acidity of substituted phenols

Phenol has a $\mathrm pK_\mathrm a$ approximately equal to $9.9$. When one studies the acidity of chlorophenols, one notices the following: First of all, chlorophenols are more acidic than phenol, ...
3
votes
1answer
2k views

Phenol protection

Would an acceptable way to protect a phenolic alcohol be through a Williamson ether synthesis? As in: 1) Deprotonating phenol with sodium hydroxide. 2) Addition of methyl iodide. 3) Deprotection ...
5
votes
3answers
2k views

Why is the para product major in the nitrosation of phenol?

When phenol reacts with nitrous acid ($\ce{NaNO2 + \mathrm{conc}\ H2SO4}$), 4-nitrosophenol and not 2-nitrosophenol is formed. I cannot understand why the para-isomer should be preferred over the ...
11
votes
2answers
3k views

Why isn't 4-hydroxybenzoic acid formed along with salicylic acid in Kolbe's reaction?

I've read that in Kolbe's reaction of phenol, i.e. reaction of phenol $(\ce {C6H5OH})$ with $\ce{NaOH}$ forming sodium phenoxide $(\ce {C6H5O^{-}Na^{+}})$, followed by reaction with $\ce{CO_2}$ and ...
23
votes
4answers
66k views

Reason for the stronger acidic property of phenol than alcohol

In phenol, pulling the $\mathrm{p}_z$ electrons from the oxygen atom into the ring causes the hydrogen atom to be more partially positive than it is in aliphatic alcohols. This means it is much more ...
24
votes
2answers
4k views

Electrophilic Aromatic Substitution: Are protonated OH-groups ortho-/para- or meta-directing?

In Electrophilic Aromatic Substitution ($\text{S}_{\text{E}}\text{Ar}$) reactions groups that can donate an electron pair into the aromatic ring, e.g. $\ce{-OH}$ or $\ce{-NH2}$, are ortho-/para-...
3
votes
2answers
2k views

Reduction of terephthalic acid to an alcohol (or phenol?)

I want to convert terephthalic acid (TPA) to an alcohol (however I think the correct term would be "a phenol"). I've read that lithium tetrahydridoaluminate ($\ce{LiAlH4}$) can produce an alcohol ...