Questions tagged [cis-trans-isomerism]
Stereoisomeric olefins, cycloalkanes, etc. which differ in the positions of groups relative to a reference plane: in the cis-isomer the atoms are on the same side, in the trans-isomer they are on opposite sides. An obsolete synonym, for which the usage is strongly discouraged, is geometric isomerism.
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Solubility of 2,3-dichlorobut-2-ene
Generally, cis isomers of alkenes have higher solubility in polar solvents as they have higher dipole moment than the corresponding trans isomers.
But according to some sources trans isomer of 2,3-...
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Is there a way to name 1,4-dimethylcyclohexan-1-ol in a way that indicates the methyl groups must be cis?
I am trying to make a IUPAC name for this molecule
that unambiguously defines its relative stereochemistry. I can't use R* and S* because there are no chiral carbons to be R or S relative to each ...
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Why is 1,2-dichlorocyclohex-1-ene not a geometrical isomer?
This was an IB question from the paper: Nov 2002 Paper 3 Option H (H2)
I am unable to understand why this compound is not a geometrical isomer because it has a ring structure, a double bond and the ...
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Bicyclic compound(s) with double bond(s) isomerism
I am aware that a bicyclic compound such as decalin can exhibit geometric isomerism.
However, for this question in my book, the answer given is 3:
(8) In given questions, how many show geometrical ...
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Comparing acidic strength of cis and trans isomers of different enoic acids
Following is the comparison of acidic strengths of cis and trans isomers of different enoic acids:
The logic I deduced after looking at (a) was that since substituents at trans position have a better ...
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Most stable conformations of the cis trans isomers of 1,3-ditert-butylcyclohexane
1,3-ditert-butylcyclohexane has two isomers of interest for this problem. Why does the trans isomer of this compound exist in a twist boat conformation while the cis one is a chair conformation?
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cis-trans Isomerism for cyclic compounds
I'm wondering why C cannot be an answer as well since we can consider the different orientations of the 2 CH3s above and below the plane of the compound. These along with different combinations of ...
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Assigning Priority in Cyclic Isomers
In a problem, I was asked to determine whether this molecule is an E isomer or a Z isomer. I didn't know much about cyclic substituents, except for extending them to acyclic digraphs. I did that, but ...
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Explanation for occurence of geometric isomerism in alkenes but not alkanes
I was reading through my chemistry textbook on isomerism for organic compounds (simple alkanes and alkenes). It explained structural isomerism for organic compounds and geometric stereoisomerism for ...
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Does 1-chloro-4-(chloromethylidene)cyclohexane show geometrical isomerism?
Would this compound show geometrical isomerism, or GI for short?
There certainly wouldn't be any restricted rotation for any atoms in the ring, as for the chiral carbon having chlorine and hydrogen (...
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Geometrical isomerism in spiro structures
The following structure shows Geometrical isomerism (GI for short) because the -Cl and -Br are in same plane
This structure does not show GI because the -Cl and -Br are in perpendicular planes and ...
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Are these stereoisomers considered geometrical isomers?
I came across this compound in the Black Book of Organic Chemistry by Ashish Mishra. The question asked whether this compound could show geometrical isomers.
Now, I know the compound has the ...
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What is the number of different compounds formed from the monochlorination of cis-1,2-dimethyl cyclopentane?
I encountered this question in the Black Book of Organic Chemistry by Ashish Mishra while preparing for a college entrance exam.
According to the answer key the answer is 12. I have only managed to ...
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Why is cyclooctene the smallest cycloalkene to have cis-trans isomerism?
What prevents cis and trans isomers from existing in smaller cycloalkenes, for example, cyclohexenes for more than a short period of time?
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Why trans-dibromoethane is more favorable than cis-dibromoethane? [closed]
2 questions:
Is trans-dibromoethane more stable than cis-dibromoethane because it's more symmetrical (in terms of molecular weight distribution on either side)?
Is it always the case that trans ...
