Table of contents

1. A Review of General Chemistry5h 5m
2. Molecular Representations1h 14m
3. Acids and Bases2h 46m
4. Alkanes and Cycloalkanes4h 17m
5. Chirality3h 39m
6. Thermodynamics and Kinetics1h 22m
7. Substitution Reactions1h 48m
8. Elimination Reactions2h 30m
9. Alkenes and Alkynes2h 9m
10. Addition Reactions3h 19m
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 Acids4h 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

8. Elimination Reactions

SN1 SN2 E1 E2 Chart (Big Daddy Flowchart)

Organic Chemistry

8. Elimination Reactions

SN1 SN2 E1 E2 Chart (Big Daddy Flowchart)

Previous problemNext problem

1:24 minutes

Problem 125

Textbook Question

What products are formed when the following stereoisomer of 2-chloro-1,3-dimethylcyclohexane reacts with methoxide ion?

Verified step by step guidance

Identify the type of reaction: The reaction involves a strong base (methoxide ion, CH₃O⁻) and an alkyl halide (2-chloro-1,3-dimethylcyclohexane). This suggests that the reaction could proceed via an elimination (E2) mechanism or a substitution (SN2) mechanism. Analyze the conditions to determine the dominant pathway.

Examine the structure of the substrate: 2-chloro-1,3-dimethylcyclohexane is a cyclohexane ring with a chlorine atom and two methyl groups attached. Determine the stereochemistry of the molecule (e.g., axial or equatorial positions of the substituents) to predict the reaction outcome.

Consider the E2 elimination mechanism: In an E2 reaction, the base abstracts a proton from a β-carbon (a carbon adjacent to the carbon bearing the leaving group). The leaving group (Cl⁻) departs simultaneously, forming a double bond. Identify the β-hydrogens that are anti-periplanar (in opposite planes) to the leaving group, as this geometry is required for E2 elimination.

Evaluate the possibility of SN2 substitution: In an SN2 reaction, the methoxide ion would attack the carbon bearing the chlorine atom, displacing the Cl⁻ group in a single step. However, steric hindrance from the cyclohexane ring and the methyl groups may make SN2 less favorable. Assess whether steric hindrance is significant in this case.

Predict the products: For the E2 pathway, determine the most stable alkene product based on Zaitsev's rule (the more substituted alkene is generally favored). For the SN2 pathway, predict the substitution product where methoxide replaces the chlorine atom. Consider the stereochemical outcomes for both pathways.

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.

Stereoisomerism

Stereoisomerism refers to the phenomenon where compounds have the same molecular formula and connectivity of atoms but differ in the spatial arrangement of their atoms. In the case of 2-chloro-1,3-dimethylcyclohexane, the specific stereochemistry (cis or trans) affects how the molecule interacts with reagents, influencing the reaction pathway and products formed.

Nucleophilic Substitution Reactions

Nucleophilic substitution reactions involve the replacement of a leaving group (like a chloride ion) by a nucleophile (such as methoxide ion). The mechanism can proceed via either an SN1 or SN2 pathway, depending on factors like steric hindrance and the nature of the substrate. Understanding these mechanisms is crucial for predicting the products of the reaction.

Cyclohexane Conformation

Cyclohexane can adopt various conformations, primarily chair and boat forms, which influence the reactivity of substituents on the ring. The stability of these conformations affects how substituents are positioned relative to each other, impacting the outcome of reactions, especially in stereospecific reactions involving nucleophiles.

Watch next

Master Overview of the flowchart. with a bite sized video explanation from Johnny

Start learning