Questions tagged [stereoelectronics]
For questions where the reactivity/conformation of the molecule is defined/controlled by a specific orbital arrangement/alignment (for example the unusual conformation of sugars because of the anomeric effect). This tag cannot be the only tag on a question. Tags such as [conformation] and [torganic-chemistry] must also be applied.
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How can the gauche-effect be explained?
Generally, anti-conformations are more stable. But in the case of 2-fluoroethanol, the gauche confirmation is more stable.
It's given in March's advanced organic chemistry book that intramolecular ...
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Why are DCM and chloroform so resistant towards nucleophilic substitution?
In the book Organic Chemistry by J. Clayden, N. Greeves, S. Warren, and P. Wothers I found the following reasoning:
You may have wondered why it is that, while methyl chloride (chloromethane) is a ...
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How are SN2 transition states stabilised by adjacent double bonds and carbonyl groups?
It is my understanding that transition states in an SN2 reaction have some filled and some empty orbital character, as we have the backside of the C-X σ* beginning to fill with electrons from the HOMO ...
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Why are lactones more acidic than esters?
Lactones ($\mathrm pK_\mathrm a \sim 25$) tend to be more acidic than esters ($\mathrm pK_\mathrm a \sim 30$). I know that the lactone is fixed in a (E)-conformation, due to the ring:
and that in ...
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Hydrolysis of Sucrose over Sn1Ac or Sn2Ac
In "March's Advanced Organic Chemistry" I have read about the general mechanism of the acetal hydrolysis. It names the acid-catalyzed SN1 or SN2 as a possible mechanism for a Acetal-hydrolysis.
Now I ...
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Which conformer of beta D-glucose is more stable?
I drew the two chair conformers of $ \beta $-D-glucose:
Which one is more stable?
I think it's the one with all of the OH groups in the equatorial position because of less steric hindrance, but I ...
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Regioselectivity in iodolactonisation of γ,δ-unsaturated carboxylic acid
In the last step of the iodolactonisation of 3,3-dimethylpent-4-enoic acid,[1,2] why does the carboxylate attack the iodonium to form a 5-membered ring, when a more stable 6-membered ring is possible? ...
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Mechanism of three-membered lactone hydrolysis in base
I was reading up on the participation of neighboring functional groups and in the reaction below, I was wondering why hydroxide attacks the C–O bond instead of the carbonyl group of the lactone. ...
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Stabilisation of carbocations through hyperconjugation
Our teachers told us that greater the number of alpha H, greater is the stability of carbocation.
But consider this:
$\ce{CH3CH2+}$ and. $\ce{CH3CH2CH2+}$
The first one has 3 alpha H ...
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