Questions tagged [hyperconjugation]
Hyperconjugation involves the donation of electrons from a filled orbital (commonly the bonding C-H sigma molecular orbital) into an adjacent/partially occupied p-orbital (for instance an adjacent carbocation) leading to stabilisation. The tag should be applied to questions where hyperconjugation is involved, even if the question does not explicitly refer to it.
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Is there hyperconjugation in alkynes?
If hyperconjugation is the donation from σ to π* donation, is it possible in alkynes? I've never seen an example, or it being discussed anywhere.
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Stability of phenylic carbocations [closed]
Problem:
Structure (1) is more stable than structure (2).
My teacher stated that Structure (1) is more stable than Structure (2). I find this confusing. How can Structure (1) be more stable when ...
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Why hyperconjugation is called as σ to π* donation for alkenes and alkynes?
Why hyperconjugation is called as σ to π* donation for alkenes and alkynes if for C2 lowest unoccupied molecular orbital is σ2p not π*2p?
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Which group is more ortho/para-directing?
Currently working on assigning the C NMR and H NMR spectra for this molecule (I believe it's called E-E bis(4-methylbenzylidene)acetone ) but I'm a bit confused as to whether the methyl group is more ...
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Why do bonds interact with other bonds and exhibit overlapping effect?
In carbocations, alkenes and carbon free radicals during hyperconjugation, overlapping of molecular orbitals take place. So how and why does this happen?
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In hyperconjugation in carbocations, which atom has more positive charge?
If we consider a carbocation, let's say $\ce{C2H3^+}$
The hypothetical hyperconjugation structures will be like this 👇
In the actual structure(i.e. the resonance hybrid, all the $3$ $\ce{H}$ atoms ...
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Effect of beta branching and carbocation rearrangement on SN1 reaction rates
My book (NCERT class 12 Chemistry) asks
Predict the order of reactivity of the four isomeric bromobutanes in SN1 and SN2 reactions.
The answer given for SN1 is
1-bromobutane < 1-bromo-2-...
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Between compounds having same functional groups, why does the one with greater -I effect have higher acidic strength
Consider the two compounds $\ce{FCH2COOH}$ and $\ce{ClCH2COOH}$.
Since fluorine is more electronegative than $\ce{Cl}$ it will show a greater –I effect.
It will pull the the electrons closer towards ...
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How is propene more reactive as well as more stable than ethene?
I know that hyperconjugation stabilises a double bond. But in propene an electron-donating group $(\ce{-CH3})$ is increasing the electron density at the double bond, so its nucleophilicity should be ...
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How does Hyperconjugation stabilize a Carbon Free Radical? [closed]
I tried drawing the resonance structures but just cannot see how donating two electrons to a carbon that only needs one electron make it more stable?
I stumbled upon this question asked years ago ...
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Why are the unsaturated fatty acids usually unconjugated?
My textbook gives the structures of the unsaturated fatty acids in food including oleic acid, linoleic acid, linolenic acid and docosatetraenoic acid. I figure that when two or more $\ce{C=C}$ double ...
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Reactivity of Alkenes with HBr [closed]
I am new in the Organic Chemistry (World of Reactions). I had got one question in my test. But, when I had seen it, I got no proper logic to tick the correct answer, and then when I saw solution, then ...
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Ortho effect and the relative acidity in aromatic acids [duplicate]
What is the order of the acidity of 2-methyl benzoic acid and 2-isopropyl benzoic acid?
I know about ortho effect which states that the acidity of ortho- substituted aromatic carboxylic acids is ...
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How come the methyl group (-CH3) is electron donating?
If the inductive effect operates purely through electronegativity differences, how come the methyl group is considered to donate electrons through the inductive effect? My textbook says that there is ...
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Why is the carbanion stability order the way it is? (3*<2*<1*)
According to the lecture notes I made, a 1* carbanion is more stable than a 3* carbanion. I can't grasp exactly why. (I had a look at the similar questions, the answers didn't help)
With my very ...
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