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. This tag should also be applied to antiaromatic compounds. This tag should not be applied to general questions about ...

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Bromination of Benzene Based Molecule

Using two equivalents of $\ce{Br2}$ and catalytic $\ce{FeBr3}$ compound A can be converted into B. In the same reaction vessel but in multiple steps the conversion of B into C ($\ce{C11H12Br3I}$) ...
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1answer
39 views

Zero dipole moment of p-dinitrobenzene

Why is $\mu=0$ for p-dinitrobenzene ? How can the dipole moments of the two Nitro groups exactly cancel each other ? Shouldn't it have a non-zero, albeit feeble, dipole moment ?
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Question about Anti-Aromatic and Non-Aromatic compounds

Why can't just all anti-aromatic systems loose planarity (and hence conjugation) and be non-aromatic like cyclooctatetraene ? ...
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38 views

A question about preparation of chlorobenzene

The best method (as I have read) for preparation of chlorobenzene is by reacting it with $\ce{Cl2}$/$\ce{FeCl3}$. Why its not the best practice to react phenol with $\ce{PCl5}$ ?
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1answer
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How do I convert 4-(Methylthio)benzaldehyde to 4-(thioacetate)benzaldehyde?

Sorry if I have the incorrect name of the final product. I'm trying to acylate the methyl mercaptan substituent to a thioester (thioacetate). I appreciate any help!
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Kinetic Isotopic Effect in EAS

It is observed that rate of reaction of two isotopologues of benzene, $\cf{C6D6}$ and $\cf{C6H6}$, is the same for electrophilic aromatic reactions, as the deprotonation is not the rate limiting step. ...
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38 views

Aromaticity & delocalization of electrons

Are these Anti aromatic/aromatic or non aromatic? 1. Here, if we were to consider the resonating structure(s) with charge separation One ring is aromatic and other is anti aromatic, and ...
3
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1answer
78 views

How to identify the number of pi electrons in a conjugated system to calculate the HOMO-LUMO gap with the particle in the box approach?

It's my understanding that for a particle in a 1-D box, the change in energy from the HOMO to LUMO can be approximated with the following equation: $$\Delta E=\frac{h^2 ( N + 1 )}{8 m_\mathrm{e} ...
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1answer
41 views

Stability of Phenoxide Ion

The Phenoxide Ion is more stable than the Phenol itself because more stabilized resonance structures. But on the other hand we say phenoxide ions are more susceptible to electrophilic attack as they ...
0
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1answer
72 views

Pyridine-N-oxide - Removal of oxygen

Under what condition do the reaction proceed with sole removal of oxygen in contrast with the product also ending up with chlorine substituent? I'm familiar with both reaction mechanism, but can't ...
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2answers
49 views

Halogen and inductive effect

background : As proved by rate of EAS, mesomeric or simply conjugated resonance is weaker for halogens than inductive and make them electron taking, with fluorine almost doing nothing due to ...
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1answer
41 views

Is chloronitrobenzene and nitrochlorobenzene same?

Is it 2-chloronitrobenzene or 2-nitrochlorobenzene? If we take nitro group as the substituent, it will be 2-chloronitrobenzene. But if we take chloro group as the substituent, it is ...
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1answer
20 views

What is exactly ortho effect in Reimmer-Timmer reaction? [duplicate]

In the Reimmer-Timmer reaction cho group is added to only at ortho position not at para position , I got the answer for this as ortho effect. So what is exactly ortho effect.
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2answers
92 views

The naming of benzene

Why is benzene not called as a cyclo triene? Wikipedia says benzene is a IUPAC name, but isn't it a common name?
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2answers
82 views

Does Friedel-Crafts Reaction fail with Benzoic acid?

I know that Friedel-Crafts reaction (Either alkylation or acylation) fails with phenol and aniline due to formation of a coordinate bond between lewis acid catalyst and lone pairs of them. But I ...
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1answer
64 views

Nucleophilic substitution mechanisms in aromatic compounds

I was reading nucleophilic substitution in Aromatic halides and it suggests two different mechanisms namely - SNAr and benzyne mechanism. However, I am confused between which one to use when trying to ...
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1answer
92 views

What is the use of “pyro” in the naming of organic compound?

Recently I asked a question on the naming of polyhydroxy phenols. One of them was pyrogallol (1,2,3-Trihydroxybenzene) which is synthesized from gallic acid obtained from oak galls. (BEWARE- not a ...
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2answers
639 views

Why is this compound named resorcinol?

Substituted phenols or polyhydroxy phenols have their general name apart form IUPAC names. The general names comes from the source it is found like:- Catechol (1,2-dihydroxybenzene)- obtained from ...
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2answers
64 views

Suggestions for reaction conditions to prepare methyl 2,4,6-trimethylbenzenesulfonate

I'm a beginner in organic chemistry and I wish to produce methyl 2,4,6-trimethylbenzenesulfonate. My reactants are 2,4,6-trimethylbenzenesulfonyl chloride (solid crystals) and methanol (solvent as ...
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1answer
31 views

The meaning of the sulfite anion attached to the benzene ring

I needed to work with PEDOT:PSS solution, so I also looked up it's chemical composition and the wikipedia page threw up this pic. I need to understand how the sulfite anion is connected to the ...
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0answers
47 views

Resonance and inductive effects [duplicate]

What happens when a phenyl group itself is attached to a benzene? What are its I and R effects? For example: NH2 shows -I and +R I want to clarify this because there seems to be an inconsistency in ...
0
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1answer
123 views

Chlorobenzene vs. Fluorobenzene

We are familiar with the structures of chlorobenzene and fluorobenzene. Both the halogens show a −I effect in which fluorine has more electron withdrawing effect than chlorine. Now, if we ...
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26 views

Priorities IUPAC [duplicate]

I have an exam tomorrow. I have a problem with name aromatics compounds. I suspect there is a priority list(chart) that we should follow on putting numbers on each branch of the benzene cycle. ...
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38 views

Where is 4-acetamidobenzoic acid and 2-aminobenzoic acid used? [closed]

I need this for a big chemestry researche work so I would be grateful if you could help me. I couldn't find a proper information on the internet.
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0answers
26 views

Variation of activating effects in different media

Why do activating effects vary in different media? Explain it using the two compounds shown below. We know that different group on benzene ring can deactivate(e.g. $\ce{-NO2}$) or activate ...
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1answer
184 views

Why is the Friedel-Crafts alkylation of nitrobenzene disfavoured?

Suggest a synthetic route to m-nitrotoluene, starting from benzene. The conversion can be achieved in two ways: $\hspace{10 mm}$ or: However, the first route is not possible as the ...
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2answers
175 views

Electron withdrawing groups and acidity

I know that a strong electron withdrawing group reduces electron density and makes a molecule more acidic. Also, a meta substituent will have less effect than ortho and para substituence and the para ...
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1answer
36 views

Why is OH group activating towards electrophilic aromatic substitution?

In phenol, the OH group has -I effect due to electronegative oxygen. So, OH group should deactivate the benzene ring towards electrophilic substitution. [P.S.: I am not talking about the ...
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1answer
105 views

What is the functional group derived from benzene called?

If you were asked in an exam to name this functional group, would you call it benzene or an aromatic hydrocarbon?
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1answer
70 views

Acidity of o-halobenzoic acids

Rank the following compounds in decreasing order of acidity: 1) 2-Fluorobenzoic acid 2) 2-Chlorobenzoic acid 3) 2-Bromobenzoic acid 4) 2-Iodobenzoic acid My approach Since the ortho ...
9
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1answer
233 views

Reaction of furan with chloroform

$\hspace{50 mm}$ This reaction looks like the Riemer-Tiemann reaction. The only difference is the reactant. First step is the formation of carbene. Second step involves the attack of $\pi$-electrons ...
3
votes
1answer
30 views

How to decide rates of SN1 reactions

What will be the order of SN1 solvolysis rates for these? $\hspace{35 mm}$ I'm confused between the second and third options. $\ce{I-}$ is a better leaving group than $\ce{Br-}$, but the carbocation ...
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1answer
129 views

Double alkylation of benzene to form ring

I have been asked to suggest a synthesis for the following compound (tetralin) from benzene: I am unsure how to do this. It surely can't be Friedel-Craft alkylation because of carbocation ...
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Frost circle method for determining aromaticity

Can the 'Frost Circle' method for determining aromaticity be used for bicyclic or multicyclic compounds???
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16 views

Origin of different colour for thio analogue of indigo from blue to red

Why the thio analogue of indigo is red? What is the reason behind change of colour from indigo to red just by change of N to S. What I get is that there will be electronegativity, lone pair ...
4
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0answers
30 views

Why does the Reimer-Tiemann reaction give an ortho product? [duplicate]

On treating phenol with chloroform in the presence of sodium hydroxide, a $\ce{-CHO}$ group is introduced at the ortho position of the hydroxy group. Why is this so? Why is 4-hydroxybenzaldehyde not ...
3
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1answer
96 views

Priority when naming benzene derivatives

I've been playing around with chemdraw and found that it assigns the priorities of substituents in a way I wouldn't have expected. I'm not a nomenclature buff, so I'd like to know if it's correct and ...
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1answer
120 views

Why is styrene an aromatic compound? [duplicate]

Why is styrene aromatic? Doesn't it have 8 pi electrons, thereby violating Hückel's rule? Can someone offer an alternate, more through explanation?
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1answer
253 views

Explain this enolisation process?

I have no idea really how to get started... Where does the hydrogen for the first deprotonation come from? My working thus far:
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0answers
74 views

Aniline & Benzene

Question: Can the benzene ring attached to aniline be detached in an aqueous solution (specifically groundwater) under certain conditions? Also would the two compounds be detected as separate entities ...
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1answer
278 views

Mechanism for chloromethylation of benzene

I have just thought of a possible mechanism: Can this work? Not your standard Friedel-Crafts alkylation reaction since the Cl in the alkyl chain is confusing! Could someone please explain?
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nitration of aromatic compound with alkyl substituent

For this compound: $\hspace{70 mm}$ What would be the products following a standard nitration with $\ce{NO2+}$? My reasoning is thus: Since the substituent group is alkyl then it is ortho- or ...
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3answers
760 views

Does Benzene's resonance structure allow it to enter DNA?

According to this link, benzene is able to insert itself into the human DNA. It isn't an authoritative source and appears to be quite biased, so I'm wondering if there's any truth to this. The ...
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1answer
74 views

Find the order of acidic strength

Arrange the following in decreasing order of acidity I think it's S>P>R>Q (Q) forms an anti aromatic conjugate base. So its the least acidic compound here. (R) forms forms a conjugate base which ...
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1answer
253 views

Why is phenyl weakly activating?

The susceptibility of a benzene ring to electrophilic attack depends on the type and number of groups bonded to the ring. Activating groups donate/release electrons and increase the electron density ...
6
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1answer
221 views

Why are aromatic compounds so stable?

I've never actually been told deeper reasons for this. In organic chemistry classes (1 and 2) we're usually told that aromatic compounds are very stable whereas anti-aromatic ones are not, and also, ...
5
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1answer
272 views

Convert benzene to isopropylbenzene

Which of the following reagents will convert benzene to isopropylbenzene? Choose all that are appropriate. I know for certain that (b) can be used, but I also think the following mechanism with ...
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0answers
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Determining the aromatic ring systems in callistephin

I am trying to figure out which are the aromatic rings and which are not in the compound Callistephin (shown below): I know the substituted benzene rings definitely are... But im not sure about the ...
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1answer
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Identifying aromatic ring systems in compounds

I'm trying to work out which are the aromatic ring systems in a complex compound called Aklavinone: I am trying to follow Hückel's rule that the compound must be: cyclic p-orbital on every atom ...