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34 votes
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Is cis-1,2-dimethylcyclohexane a meso compound?

cis-1,2-Dimethylcyclohexane is achiral, not because there is a plane of symmetry, but because it consists of two enantiomeric conformations which interconvert rapidly via ring flipping at normal ...
orthocresol's user avatar
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14 votes
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Why is diequatorial trans-1,2-dimethylcyclohexane more stable than diaxial trans-1,2-dimethylcyclohexane?

The key concept is 1,3-diaxial interaction. See the figure 1 below using methylcyclohexane as an example. Figure 1: Equatorial and axial conformations of methylcyclohexane with 1,3-diaxial strain ...
Jan's user avatar
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13 votes

Is cis-1,2-dimethylcyclohexane a meso compound?

I'd like to add a few points definition wise from the IUPAC goldbook. (Because recently the original website seems to be broken I am using links via the internet archive.) meso A prefix to ...
Martin - マーチン's user avatar
8 votes
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Decarboxylation / Elimination type reaction

This type of reaction falls into the category of Grob fragmentation [Wikipedia]. Conceptually, it is very similar to an E2 mechanism, where an anti-periplanar pair of electrons flows into the sigma ...
jerepierre's user avatar
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8 votes
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What would this unsaturated cyclic compound be called?

Chemspider tells me that the name should be 1,1'-Bi(cyclohexylidene) http://www.chemspider.com/Chemical-Structure.121798.html?rid=e40cd595-d5e5-450e-bdb3-3e558a9da92d While PubChem mentions: ...
Berry Holmes's user avatar
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8 votes

Stereochemistry of 1,4 disubstituted cyclohexane

Take the molecule on the left and ideally flip it by rotating 180 degrees along the vertical axis of the diagram. This inverts the cyclohexane without having to break or modify the molecule in any way
Nicola Sap's user avatar
8 votes
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Why was Nobel Prize given to Baeyer for his "faulty" Baeyer's Strain Theory?

Scientists are human beings after all. Nobody gets a Nobel Prize for inventing a "formula". It is the idea that makes an impact and new ideas are respected. Scientists like normal human beings make ...
AChem's user avatar
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8 votes
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Steric effect of t-butyl group on SN1 on a cyclohexane ring

I would argue that the reasoning makes sense. There are some important things to discuss here. The cis isomer ($C$) and the trans isomer ($T$) will both react via the same carbocation intermediate. ...
Zhe's user avatar
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7 votes
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Can a boat conformer of cyclohexane be most stable?

TL;DR: It is highly unlikely that there is a non-multicyclic derivative with a stable boat conformation. It needs a lot of convincing and quite bulky groups to destabilise the chair conformation and ...
Martin - マーチン's user avatar
7 votes

Most stable conformational isomer of 3-methoxycyclohexan-1-ol

Sometimes, the intuitive rule of thumb that favours conformations with $\ce{OH}$ substituents in equatorial positions miserably fails. For 1, a cyclization product of geranyl acetate, one might ...
Klaus-Dieter Warzecha's user avatar
7 votes

Effect of periodic acid on cyclohexane derivatives

The literature reveals that cis-1,2-cyclohexanediol 1 cleaves about 20-times faster than trans-1,2-cyclohexanediol 2 although the equilibrium between the diol and the cyclic periodate intermediate ...
user55119's user avatar
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6 votes

Can wedge and dash bonds on 1, 2 position of cyclohexane ring be used to signify trans orientation of the substituents?

So if you drew a wedge in position 1 and a dash in position 2, it would mean that they are on the same plane - either both axial or both equatorial - assuming that the ring was in a chair conformation....
IT Tsoi's user avatar
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6 votes

Most stable chair conformation

The lowest energy conformer for a cyclohexane ring with multiple substituents will be the one in which the largest group occupies an equatorial position. Steric parameters are tabulated in many ...
NotEvans.'s user avatar
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6 votes
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Cyclohexane derivative formation of carambolaflavone using a Lewis acid catalyst

@Waylander provided a correct written explanation for your question. I'll expand on his comments by considering the effect of temperature and provide diagrams. Using M+ = Sc+3 to save some space, the ...
user55119's user avatar
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6 votes
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Is cyclohexane‐1,3‐dicarboxylic acid a correct IUPAC name?

The answer to this question is actually pretty interesting, I think. @user55119 's comment that the principal chain is the cyclohexane ring is correct -- but it seems like you understand that that's ...
George's user avatar
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5 votes

Is cyclohexane saturated or unsaturated?

Cyclo comes from the Greek word 'kyklos' which means circle. The cyclohexane molecule is in the form of a circle therefore it can have the formula $\ce{C_nH_{2n}}$ and still be saturated.
CKA's user avatar
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Most stable conformational isomer of 3-methoxycyclohexan-1-ol

I would say that the answer to the question depends strongly on the solvent used. In case anybody still doesn’t see it: in the orientation (d), the compound can form an intramolecular hydrogen bond ...
Jan's user avatar
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5 votes
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Best chair configuration for trimethylcyclohexane matching a specific Haworth projection?

While you are correct that B should be the most stable conformer of trimethylcylcohexane, the question asked which one best represents the one shown in the Haworth projection. Answer choice B has R ...
Niels Kornerup's user avatar
5 votes

Stability of cyclohexane type species

According to the Ref.1, 5-hydroxy-1,3-dioxane (the compound of structures V and VI) both in the gaseous state and in dilute $\ce{CCl4}$ solution exists as a chair conformer, the hydroxy group in an ...
Mathew Mahindaratne's user avatar
5 votes
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Ring Flip of glucose

The short answer is no. Experiment with a model kit (example) and recognize changing conformers only is about wiggling/rotating bonds which may be gradual in many tiny steps. The transition from one ...
Buttonwood's user avatar
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5 votes
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Why 5-member rings prefer being cis-fused?

tldr; I think it's pretty close between the two forms - at least for unsubstituted hydrocarbons Since we just worked on a project to understand ring puckering conformations, I was curious about this. ...
Geoff Hutchison's user avatar
4 votes
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Is the SN1 reaction faster with an axial or equatorial leaving group?

In compund 2, both substituents can be placed in equatorial positions, whereas in 1 the $\ce{Cl}$ group is forced into an axial position since the bulky t-butyl group has to be placed equatorial. This ...
Variax's user avatar
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4 votes
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Diastereoselectivity in synthesis problem (4 stereocenters)

If we get rid of the two methyl groups and just consider what the 3D conformation of the molecule is likely to be (I don't have a pen on me right now, but the model below was minimised using very low ...
NotEvans.'s user avatar
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4 votes
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Synthesis of methylenecyclohexane from cyclohexylmethanol

Whichever method of elimination you end up preferring, there is no way to directly eliminate the hydroxy group without derivatising it first in some way. The hydroxide ion is a very bad leaving group (...
Jan's user avatar
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4 votes
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Can exact bond angles in cycloalkanes be calculated?

There may be experimental data for the specific cycloalkane in question, for example by a single-crystal diffraction analysis. Beside entries in the primary literature, there are databases with the ...
Buttonwood's user avatar
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3 votes

Is boat form of cyclohexane non polar?

Being nonpolar does not require having the zero dipole moment. Enough is being much closer to having a zero dipole moment than to having the a strong dipole moment. It applies also to parts of the ...
Poutnik's user avatar
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3 votes
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Heat of hydrogenation of 1,3-substituted cyclohexanes

First of all, as Jan pointed out on the comment, better nomenclature for thes compounds is syn- and anti- instead of cis- and trans-, respectively. However, OP is more familiar with cis- and trans- ...
Mathew Mahindaratne's user avatar
3 votes

What would this unsaturated cyclic compound be called?

It's called cyclohexylidenecyclohexane.
gannex's user avatar
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3 votes

How to determine the stereochemistry after elimination of anti-1-bromo-2-methylcyclohexane?

You diaxial intermediate is good and you can clearly see that there is no way to achieve a Zaytsev product in an $\mathrm{E2}$ elimination since that would require eliminating the methyl group. Carry ...
Jan's user avatar
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