Concept explainers
Interpretation:
The amount of steric strain in each of the chair conformers of
Concept introduction:
Strain energy: Ring strain is a type of instability that exists when bonds in a molecule form angles that are abnormal. Strain is most commonly discussed for small rings such as cyclopropanes and cyclobutanes, whose internal angles are substantially smaller than the idealized value of approximately 109°.
Angle strain of cyclic molecules: The German chemist Adolf van Baeyer, believing that all cyclic molecules like planner, proposed that the stability of a cycloalkane could be predicated by determining the difference between this ideal bond angle and the bond angle in the planner cycloalkane.
We consider the simple example of the bond angle in cyclopropane are 600 degree repressing a 45.50 degree it deviation from 109.50, it is proved from Baeyer this deviation cause angle strain which decrease respective molecules stability.
The corresponding Bond strain formula shown below
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Essential Organic Chemistry (3rd Edition)
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- Construct the chair structures with the molecular models for trans-1-ethyl-3-methylcyclohexane. Find the energy of each conformer, the equilibrium constant Keq, and the percentage of each conformer at 25oC. Indicate which conformer is more stable.arrow_forward13 Draw the molecule trans-1-ethyl-3- isopropylcyclohexane conformation. Which is the overall most-stable conformer? Justify your answer. in its chair and its flipped chairarrow_forwardProvide the least stable(highest energy) chair conformation of chlorocyclohexane.arrow_forward
- Organic ChemistryChemistryISBN:9781305580350Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. FootePublisher:Cengage Learning