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.
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Why is m-fluorophenol less acidic than m-chlorophenol?
Why is m-Fluorophenol less acidic than all the other m-Halophenols, even though it has the most inductive effect
The data is from :
A guidebook to Mechanism in organic chemistry for the JEE, 6th ...
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How does polarity increase when electron density in oxygen decreases when comparing acidity
My book says the following statement:
Due to the higher electronegativity of $sp^{2}$ hybridized carbon of phenol , the electron density in oxygen decreases. This increases polarity of O-H bond and ...
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Intermediates in aqueous bromination of phenol
A question in my book (an archive for IIT JEE exam questions) asks:
In the reaction:
The intermediate(s) is/are?
The correct answers are given as
However, as per my knowledge, compound (b) does not ...
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Predict the products of organic reaction sequence
This is a reaction sequence involving alcohols, phenols, halides, alkenes ,alkanes etc , and the task is to identify all the compounds A to E
The few things I was able to identify :
The compound C ...
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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-...
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What happens to the NMR of an alcohol when D2O is added?
What difference you expect in the 1H NMR spectrum of phenol in $\ce{CDCl3}$ after a drop of $\ce{D2O}$ is added to the test tube?
1) Since the $\ce{-OH}$ of the phenol is quite acidic, it undergoes ...
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Why doesn't the acetic anhydride moeity react with the nucleophilic carbonyl oxygen of salicylic acid?
I know that salicylic acid with acetic anhydride under acidic conditions gives acetylsalicylic acid (aspirin). But my question is, why is it that post the protonation of carbonyl oxygen of acetic ...
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Why is phenol more acidic than aniline?
I find that there are two contradicting factors at play here:
1) On removing proton, negative charge on oxygen is more stable than it is on nitrogen (because of greater electronegativity of oxygen). ...
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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 ...
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Does boric acid really rearrange phenols?
This reaction was on prepchem.com and I want to know whether it could work. Most of their reactions are well sourced but this is rather scant (and can't find the patent referenced).
It is possible ...
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Reduction of gingerol content in ginger using kitchen equipment
The single topic that this question focuses on is - how to remove gingerol and only gingerol from a piece of ginger in a manner that it remains safe to eat using equipment found in a well stocked ...
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Can we convert phenol to para-nitrophenol via nitrosophenol?
Our class 12 text book says that if we treat phenol with mixture of concentrated $\ce {HNO3}$ and $\ce{H_2SO_4}$, instead of nitration, the ring is oxidized to quinone.
So, the book proposes that we ...
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How does phenol show tautomerism?
I read that atleast one alpha carbon has to be sp3 wrt the functional group (and has to have atleast 1 alpha Hydrogen atom) for it to show tautomerism.
I am able to see that in the keto isomers of ...
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Friedel–Crafts reaction of phenol
Does phenol undergo Friedel–Crafts reactions or does it react with Lewis acids like aniline does?
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Natural preservatives of ink
Would pure compounds like thymol, carvacrol, and cinnamaldehyde work as preservatives of fountain pen ink? I'm specifically interested in three properties -
Prevention of growth (mostly fungal) in ...
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Is formation of cyclic carbonate from trimethyl orthoformate and vicinal aromatic 1,2-diol possible? [closed]
Hello, my question is, "is it possible cyclic carbonate formation between trimethyl orthoformate and vicinal aromatic 1,2-diol"
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Acidification of a vicinal diol [duplicate]
The following is a question from Advanced problems in organic chemistry by MS Chouhan:
The options given are:
My initial thought was that this could be a pinacol–pinacolone rearrangement. However ...
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Why does p-nitrophenol give sodium bicarbonate test, but o-nitrophenol does not?
Both ortho- and para-nitrophenol are less acidic than carbonic acid. But still paranitrophenol reacts with sodium bicarbonate to give carbonic acid and sodium paranitrophenoxide.
However, this is not ...
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Help with mechanism: Isomerization of eugenol
I'm confused about the mechanism for the isomerization of the external alkene eugenol to the internal alkene isoeugenol. I've added an image below of their structures.
The reaction is usually carried ...
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Why is acetic acid more acidic than phenol?
Acetic acid (ethanoic acid, $\mathrm pK_\mathrm a \approx 5$) is more acidic than phenol ($\mathrm pK_\mathrm a \approx 10$), which is reflected in their reactivity with a weak base such as sodium ...
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What are the resulting conjugate acid and base of phenol and 4-nitrophenol
I have to complete the equation
4-nitrophenol + phenol --->
and then label the acid, the base, the conjugate acid and the conjugate base.
I think the answer ...
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Reaction mechanism of formation of salicylic acid with Phenol and carbon tetrachloride in basic medium?
With classic Reimer-Tiemann reaction a variation is also given in my lecture notes which use carbon tetrachloride instead of chloroform. But to me, it seems like it would be just a substitution ...
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Identifying products [duplicate]
How to determine the major and minor products in a reaction? What factors are useful to do so?
For ex: Nitration of phenols, gives the ortho nitro phenol as the the major product and para nitro phenol ...
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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 ...
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Mechanisms for Reimer-Tiemann and Kolbe-Schmidt reaction on deuterium labelled phenol
I was solving a bunch of reactions when I encountered the following:
So for the first question:
This is a Reimer-Tiemann reaction. I felt that the tautomerism would result in the deuterium getting ...
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Comparing acidic strengths between benzylammonium ion and phenol
Question
Compare the acidic stengths between benzylammonium ion and phenol.
I first tried to remove the H+ ion from both of them and tried to compare the relative stabilities of resulting conjugate ...
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Mechanism of formaldehyde / phenol condensation
The production of bakelite using this method, but with an acid as the catalyst is simple enough; a protonation of the carbonyl oxygen, followed by an electrophilic substitution to the ring. The ...
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What does acidity of para-alkyl substituted phenols depend on?
Problem
Arrange the following organic compounds in decreasing order of acidity.
Answer
Question
According to my knowledge the answer should be P, Q, R, S. As we proceed from P to S we are ...
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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?
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Is there a way to convert aniline to phenol without diazotizing it?
I am a high school student and while reading about reactions on amines, I was trying to figure out a way to convert aniline $(\ce{C6H5NH2})$ to phenol $(\ce{C6H5OH})$ without diazotizing it with ...
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DIY lipid nanoparticles
I, and a number of friends, take a bunch of supplements that are polyphenols and often flavin-oids, -ols or -es; also numerous carotenoids. Examples include quercetin, luteolin, fisetin, curcumin, ...
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Halogenation of Phenol [closed]
Why does only one $\ce{Br+}$ ion get generated in a non-polar solvent (such as $\ce{CS2}$), while more $\ce{Br+}$ ions are generated in aqueous or polar solvent (such as $\ce{H2O}$)?
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How is phenolic resin made? [closed]
The following chemical structure is phenolic resin. How is this chemical made?
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Meaning of "Nonyl-phenol 10 mole"
In my workplace we are purchasing "Nonylphenol 10 mole" and "Nonylphenol 30 mole" for use as non-ionic surfactants.
At first I assumed, because of the name, that the substance was ...
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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.
...
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Why is quinone mono oxime more stable than 4-nitrosophenol?
When we do nitrosation of phenols, we get para-nitrosophenol as the major product, which tautomerises to quinone mono oxime. This article states that it largely exists in the quinonoid form.
My ...
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Comparison of boiling points of para-derivatives of phenol
The boiling points of four para-derivatives of phenol are:
How can we compare the boiling points of p-nitrophenol and p-aminophenol?
Apart from the hydroxyl group, p-nitrophenol has two oxygen atoms ...
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Which one out of a keto group or a hydroxyl group would get protonated first if both are present in a compound (attachment)
In the solution provided by my teacher he protonated the ketone, moved the +ve above by resonance did methyl shift and then did dehydration to form a benzene type system. Is this only because for this ...
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Mechanism of Hypervalent Iodine Phenolic Coupling
I need some help understanding the hypervalent iodine phenolic coupling reaction taking place in this synthesis of morphine, the reaction uses $\ce{PhI(OAc)2}$ as the hypervalent reagent and ...
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Strong activation of phenoxide ion compared to others
I was told that in phenoxide ion, benzene ring is very strongly activated. The order my teacher told me was phenol < amine < $2^\circ$-amine < $3^\circ$-amine < phenoxide (for activation ...
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Reaction mechanism of rearrangement
I am currently studying for my organic chemistry exam, but there is one problem I do not understand. Unfortunately, I do not have any solutions.
See image for the problem.
My first thought was the ...
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How to determine the order of acidity of the following dimethyl nitrophenols
This is how I went about it, although I got a wrong answer:
3,5-Dimethyl-4-nitrophenol (2) shows the nitro group to be sterically hindered, due to which it should go out of plane and this will be an ...
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Reaction between phenol and nitrous acid
My question is about the products formed when phenol reacts with nitrous acid. I googled it and reached this PubChem paper (DOI: 10.1016/S0045-6535(02)00857-3), which states:
It was found that ...
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How much oxygen is used up by the browning of an apple?
This is inspired by a recent popular question on Cooking.
Let's assume that I take some apples, cut them up, and place them in a hermetically sealed container. Then the container goes into the fridge. ...
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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)...
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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 ...
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What is the order of acidic strength among phenol, catechol, resorcinol and hydroquinone?
This question is from a book that gives the answer as
$$
\text{hydroquinone} < \text{resorcinol} < \text{phenol} < \text{catechol}
$$
but does not provide any explanation for the answer. If ...
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Fries Rearrangement Products
During Fries Rearrangement, oxygen donates its lone pair to $\ce{AlCl_3}$ forming $\ce{-O^+-AlCl3}$. Since this is a strong electron withdrawing group, shouldn't the final product be meta-substituted?
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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 ...
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ortho/para-Selectivity in the Reimer-Tiemann Reaction [duplicate]
I can't figure out why the dichlorocarbene molecule produced in the Reimer-Tiemann reaction gets attached to the ortho position of phenol.
The ortho position is sterically slightly more hindered due ...
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