A conjugated ring of unsaturated bonds, lone pairs, or empty orbitals which exhibit a stabilization stronger than would be expected by the stabilization of conjugation alone.

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what is the origin of the colour of azo dyes?

what is the origin of the colour of azo-dyes? Is it the same reason as to why transition metal complexes have colour?
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1answer
48 views

Steam distillation- how it actually works?

To obtain phenylamine after it is formed from the reduction of nitrobenzene with tin, we carried out steam distillation. This is what I learned in class: "During the process,steam is injected ...
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2answers
198 views

reason for the stronger acidic property of phenol than alcohol

"In phenol, pulling the $p_z$ 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 easily ...
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2answers
78 views

Does benzene have isomers and resonance structures?

Does benzene have both isomers and resonance structures? I know that it has resonance structures because you can manipulate the position of the double bonds but what about isomers?
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3answers
74 views

Reasons for dry conditions in substituition reactions with benzene

All substitution reactions of benzene must be carried out in dry conditions with a catalyst that produces a powerful electrophile. This was a statement from my book. My question is, why must it ...
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3answers
184 views

Benzene and resonance

In my book, to explain the structure of benzene, it referred to the idea of resonance: "The idea of resonance is that actual molecule is a definite structure that is a hybrid of two theoretical ...
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1answer
581 views

Why use glacial acetic acid in bromination of anisole?

In my organic chemistry lab (next week, the experiment has not been conducted yet) we are being asked to react anisole with bromine to get 2-bromoanisole (as well as 2,4-dibromoanisole and all the ...
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2answers
48 views

Formation of 3-chloromethylbenzene VS 3-chloromethylbenzene VS 4-chloromethylbenzene

For methylbenzene (with the methyl group at position 1), is it easier for chlorine to substitute the hydrogen at position 2, 3 or 4? I was thinking somewhere along the lines of different charge ...
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1answer
63 views

Thermodynamic stability of benzene ring

In learned that when benzene undergoes hydrogenation, $208KJ$ of energy is given off and thus $152KJ$ less energy than what would be given off if Kekule's structure was correct. My confusion is that ...
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33 views

delocalised electrons and benzene's stability

In most high school chemistry books, it is said that the delocalised electrons in benzene makes it particularly stable. However, how does it contribute to stability? Is there any simple way of ...
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1answer
92 views

Which is better leaving group

How can I compare the leaving group ability of $Br^+$ and $Cl^+$ ions for the electrophilic substitution reactions for aromatic compounds?
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1answer
113 views

What does it mean by degree of aromaticity of a molecule?

This is a fundamental question, though I didn't really get the meaning/idea what does it mean by aromaticity or degree of aromaticity. Does it mean the ability of a molecule to be aromatic?
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2answers
172 views

How to distinguish between benzyl chloride and chloro benzene?

If I add $aq. \ce{KOH}$ to both of the compounds substitution takes place in the case of benzyl chloride and then if I oxidize with $\ce{KMnO4}$ I will get benzene carboxylic acid which will give ...
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1answer
64 views

Is aromaticity of the 4 aromatic amino acids affected by pH?

During a discussion of NMR, my lecturer told me to think about which amino acids contain protons in an aromatic ring, and whether any are likely to be affected by changes in pH. The 4 aromatic amino ...
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2answers
62 views

Where do things connect in EAS reactions?

If you have an aromatic ring that requires substitution of some molecule, how do you know where this molecule is supposed to substitute on the ring? In (i) and (ii) how do we select the ring and ...
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1answer
319 views

Resonance of benzoic acid

My book says that benzoic acid does not show resonance as the carboxylate ion and the benzene ring are not in the same plane due to steric effects. But there aren't any large group in the ortho ...
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2answers
422 views

Ozonolysis conditions for Benzene

What are the precise conditions under which Benzene undergoes ozonolysis? All anyone can tell me is that it undergoes ozonolysis under "vigorous" conditions. But, what vigorous conditions?
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0answers
35 views

Relative basicity of Toluidines and Nitro anilines

I have searched a lot of that in Internet. But I can't find a relevant answer. My question is about Relative basicity of different types $(O, M, P)$ toluidines and Nitro anilines or more specifically ...
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3answers
202 views

Reaction of Benzene with 2-methylpropene?

I'm studying organic chemistry at the moment and it's really confusing. What could ever happen between benzene and an alkene? and why is $\ce{H2SO4}$ there?
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247 views

Competing resonance and inductive effects in a substituted benzene

A molecule of phenol is much more inclined to under go an electrophilic substitution reaction than a molecule of benzene because the -OH group is highly reaction favoring. From what I understand, this ...
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1answer
78 views

Is the reactivity of Benzene with an $-N(R)_3^+$ group greater than its reactivity with an $-NH_3^+$ group?

Both are m-directors, and Electron Withdrawing groups, but which one is more reactive? At first sight, one might think clearly $\ce{-N(R)_3^+}$ is more reactive, but when you factor in that $\ce R$ is ...
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1answer
297 views

Why are halogens ortho para directing even though deactivating?

Halogens bonded to benzene ring has three lone pairs. These three electron pairs can cause resonance in benzene ring. But, halogens are also highly electronegative and thus they have strong -I effect. ...
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1answer
80 views

How are the following aromatic?

I'm not able to understand how the following are aromatic. My first doubt is whether I have to include the lone pair of electrons while applying the Huckel Rule to these compounds? If yes, then in ...
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1answer
86 views

Will this reaction lead to diazonium chloride?

Usually $\ce{NaNO2}$ and $\ce{HCl}$ is used to make diazonium chloride. But, in this compound there are two amine groups adjacent to each other so I doubt that diazonium chloride would form. Will ...
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2answers
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Why is ethanoic acid more acidic than phenol?

They say ethanoic acid is more acidic than phenol since the former can neutralize alkalis like NaOH, however, latter cannot. But if we look into the structure of ethanoate ion and phenoxide ion, the ...
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1answer
210 views

Is there any special rules for checking the aromaticity of polycyclic compounds?

This question arose in my mind because it's given in a book that pyrene is aromatic. How can it be with 16 π electrons? So, it should be actually anti-aromatic or is there any special rule for these ...
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1answer
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Lines on inside of hexagonal shapes of structure diagrams

just a simple question from me today... I was looking at the structure of Norepinephrine for a school project and was curious about the diagrams on the Wikipedia page for it. I was wondering why ...
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156 views

aromatic nucleophillic substitution?

In aromatic nucleophilic substitution why does $\ce{F-}$ acts as the best L.G.? The reason I think is due to -I effect of fluorine being the greatest it leaves first. ((As it stabilizes messienmier ...
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1answer
427 views

reaction of toluene?

**Reaction of toluene at high temp gives us (o-m)toluene whereas at normal conditions of electrphillic attack it gives us (o-p) directing . Why this happens at high temp although as methyl group is ...
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2answers
175 views

Question regarding comparing different chemical's most acidic protons?

I am burning through some test prep and have a chem question that is troubling me. The questions is as follows: How would you compare the acidity of the most acidic proton in each of the following ...
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1answer
192 views

What is the influence of an alkyl-hydroxy group on a benzene ring?

We all know that an $\ce{NO2}$ group attached to a benzene is a deactivator, and it directs and substituents that would be adding to the meta position to the $\ce{NO2}$. For an alkyl group attached ...
3
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1answer
171 views

What is the substituent on this benzaldehyde? (MS attached)

I have no clue what the substituent may be. The molar mass of the unsubstituted benzaldehyde is 105g/mol (subtracting one H, where the substituent will be). So the substituent is around 30-33g/mol. ...
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2answers
2k views

How does Sodium Bicarbonate act as a Deodorizing agent?

I was reading this other question on the site: Deodorizing using baking powder instead of baking soda. Apparently, baking soda is used quite often as a cleaning and deodorizing agent. From what I ...
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187 views

Why aren't lower aromatic organic compounds taught?

Why aren't aromatic compounds with 3, 4 or 5 carbon atoms taught at high school level chemistry? We are instead directly taught about aromatic compounds with 6 carbons/benzene rings. Why? My core ...
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1answer
75 views

Help Identifying Chemicals

I was trying to isolate elemental bismuth from pepto bismol (bismuth subsalicylate) using the process seen here but after I added the HCl, instead of getting a pink foamy substance I got a white ...
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1answer
272 views

How do you Benzylate (add a benzene group to) cyclic compounds?

How do you add a benzene group to cyclic compounds like piperidine, piperazine and phenyl derivatives? Piperidine Piperazine
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1answer
314 views

What is the name of the “primary” carbon in a benzene derivative?

If we have a benzene with a single substituent, such as chlorobenzene, what do we call the carbon atom to which the group is attached? I'm familiar with the ortho- meta- para- nomenclature, but the ...
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5answers
147 views

Why are smoke odors persistent in fabrics?

Obviously smoke is very complex, but apparently phenol compounds are the main components of wood smoke that produce the characteristic odor. (One of more significant of these compounds seems to be ...
6
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1answer
109 views

What does the charge distribution around a Stone-Wales defect look like?

I'm reading a book on carbon nanotubes (P.J.F. Harris, Carbon Nanotube Science, to be specific) at the moment and puzzling about Stone-Wales or 5775 defects. This is where two adjacent carbons undergo ...
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1answer
182 views

Why does benzene bend in this reaction?

From here I can see why hapticity changes here, but not why it is necessary for the benzene ring to bend. The resonance energy of benzene is pretty large, and there's no balancing increase in ...
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3answers
294 views

Why are arenes with conjoined benzene rings drawn as they are?

Whilst we are taught to represent benzene as below (A) due to its delocalised electrons, however when two benzene rings share carbons (e.g. naphtalene) it seems to be more commonly represented in ...
11
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1answer
224 views

Do terminal amides participate in $\pi$ stacking?

In a crystal structure I've determined, a triazole ring on my ligand appears to be stacking with a tyrosine (top in picture): However, there is also an amide, courtesy a glutamine, near it ...
15
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2answers
840 views

Why does nitration yield a meta product in this reaction?

When N,N-dimethylaniline is reacted with $\ce{H_2SO_4}$ and $\ce{HNO_3}$ it gives mainly the meta product, even though $\ce{NMe_2}$ is an ortho / para directing group. Why is this?