Concept explainers
(a)
Interpretation:
TThe two possible chair conformations for the cis-1-isopropyl-3-methylcyclohexane should be drawn and named every substituent as axial or equatorial and most stable conformer should be selected.
Concept introduction:
when the cyclohexane ring converts from one chair conformation to another, the equatorial hydrogen atoms are converted into axial hydrogen atoms and vice versa.
When the cyclohexane has one substituent then the conformation which contain the substituent in equatorial position is more stable due to less steric strain with axial hydrogen atoms.
When two substituents are present in the structure, in order to find the more stable conformation can be determined by looking at the groups in the axial position.
When a bulkier group present in the axial position, that conformation get less stable.
In cis conformation, both substituents are in the same side.
(b)
Interpretation:
The two possible chair conformations for the cis-4-tert-butylcyclohexanol should be drawn and named every substituent as axial or equatorial and most stable conformer should be selected.
Concept introduction:
when the cyclohexane ring converts from one chair conformation to another, the equatorial hydrogen atoms are converted into axial hydrogen atoms and vice versa.
When the cyclohexane has one substituent then the conformation which contain the substituent in equatorial position is more stable due to less steric strain with axial hydrogen atoms.
When two substituents are present in the structure, in order to find the more stable conformation can be determined by looking at the groups in the axial position.
When a bulkier group present in the axial position, that conformation get less stable.
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General Chemistry: Principles and Modern Applications, Loose Leaf Version (11th Edition)
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