Table of contents

1. A Review of General Chemistry5h 5m
2. Molecular Representations1h 14m
3. Acids and Bases2h 46m
4. Alkanes and Cycloalkanes4h 19m
5. Chirality3h 39m
6. Thermodynamics and Kinetics1h 22m
7. Substitution Reactions1h 48m
8. Elimination Reactions2h 30m
9. Alkenes and Alkynes2h 9m
10. Addition Reactions3h 18m
11. Radical Reactions1h 58m
12. Alcohols, Ethers, Epoxides and Thiols2h 42m
13. Alcohols and Carbonyl Compounds2h 17m
14. Synthetic Techniques1h 26m
15. Analytical Techniques:IR, NMR, Mass Spect7h 3m
16. Conjugated Systems6h 13m
17. Ultraviolet Spectroscopy51m
18. Aromaticity2h 34m
19. Reactions of Aromatics: EAS and Beyond5h 1m
20. Phenols55m
21. Aldehydes and Ketones: Nucleophilic Addition4h 56m
22. Carboxylic Acid Derivatives: NAS2h 51m
23. The Chemistry of Thioesters, Phophate Ester and Phosphate Anhydrides1h 10m
24. Enolate Chemistry: Reactions at the Alpha-Carbon1h 53m
25. Condensation Chemistry2h 9m
26. Amines1h 43m
27. Heterocycles2h 0m
28. Carbohydrates5h 53m
29. Amino Acids3h 20m
30. Peptides and Proteins2h 42m
31. Catalysis in Organic Reactions1h 30m
32. Lipids 2h 50m
33. The Organic Chemistry of Metabolic Pathways2h 52m
34. Nucleic Acids1h 32m
35. Transition Metals6h 14m
36. Synthetic Polymers1h 49m

4. Alkanes and Cycloalkanes

Cis vs Trans Conformations

Organic Chemistry

4. Alkanes and Cycloalkanes

Cis vs Trans Conformations

Previous problemNext problem

5:52 minutes

Problem 3g

Textbook Question

Use your results from [PROBLEM 3-27] to complete the following table . Each entry shows the positions of two groups arranged as shown. For example, two groups that are trans on adjacent carbons (trans-1,2) must be both equatorial (e,e) or both axial (a,a).

Verified step by step guidance

Identify the stereochemical relationship between the two groups on the cyclohexane ring.

Recall that in a cyclohexane chair conformation, groups can be in axial or equatorial positions.

Understand that for groups that are trans on adjacent carbons (trans-1,2), they must both be in equatorial (e,e) or both in axial (a,a) positions.

Consider the stability of the chair conformation: equatorial positions are generally more stable due to less steric hindrance.

Use your results from [PROBLEM 3-27] to determine the specific positions (axial or equatorial) for each entry in the table.

Verified video answer for a similar problem:

This video solution was recommended by our tutors as helpful for the problem above

Video duration:

Play a video:

Was this helpful?

Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Conformational Isomerism

Conformational isomerism refers to the different spatial arrangements of atoms in a molecule that can be interconverted by rotation around single bonds. In cycloalkanes, this is particularly important as the orientation of substituents can significantly affect the stability of the molecule. Understanding the equatorial and axial positions of substituents is crucial for predicting the most stable conformations.

Axial and Equatorial Positions

In cyclohexane and similar structures, substituents can occupy two distinct positions: axial (pointing up or down from the ring) and equatorial (pointing outward from the ring). Axial positions can lead to steric strain when larger groups are present due to 1,3-diaxial interactions, while equatorial positions are generally more stable for larger substituents. Recognizing these positions is essential for analyzing the stability of different conformations.

Trans and Cis Configurations

Trans and cis configurations describe the relative positioning of substituents on adjacent carbon atoms in a cyclic structure. In a trans configuration, substituents are on opposite sides, while in a cis configuration, they are on the same side. This distinction is important for understanding the spatial arrangement of groups and predicting the resulting conformational stability in cyclic compounds.