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

4. Alkanes and Cycloalkanes

Naming Alkenes

Organic Chemistry

4. Alkanes and Cycloalkanes

Naming Alkenes

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5:32 minutes

Problem 7c,d

Textbook Question

The following names are all incorrect. Draw the structure represented by the incorrect name (or a consistent structure if the name is ambiguous), and give your drawing the correct name.
c. 2-methylcyclopentene
d. 6-chlorocyclohexadiene

Verified step by step guidance

Step 1: Understand the structure implied by the incorrect name '2-methylcyclopentene'. Cyclopentene is a five-membered ring with one double bond. The '2-methyl' suggests a methyl group attached to the second carbon of the ring.

Step 2: Draw the structure of cyclopentene. Start by sketching a five-membered ring and place a double bond between any two adjacent carbons.

Step 3: Add the methyl group to the second carbon of the cyclopentene ring. Number the carbons in the ring starting from the double bond to ensure the methyl group is correctly placed.

Step 4: Recognize that the name '2-methylcyclopentene' is incorrect because the double bond should be at the lowest possible number. The correct name should reflect the position of the double bond and the substituent.

Step 5: For '6-chlorocyclohexadiene', recognize that cyclohexadiene is a six-membered ring with two double bonds. The numbering should start from the position that gives the lowest numbers to the double bonds. Since '6-chloro' is not possible in a six-membered ring, redraw the structure with the chlorine at a valid position and provide the correct name based on the lowest numbering for the double bonds and substituents.

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Key Concepts

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

IUPAC Nomenclature

IUPAC nomenclature is a standardized system for naming chemical compounds. It ensures that each compound has a unique name based on its structure, including the identification of the longest carbon chain, functional groups, and substituents. Understanding this system is crucial for correctly naming organic compounds and identifying errors in given names.

Cycloalkenes

Cycloalkenes are cyclic hydrocarbons containing one or more carbon-carbon double bonds. The naming of cycloalkenes involves identifying the position of the double bond and any substituents. For example, '2-methylcyclopentene' suggests a methyl group on the second carbon of a five-membered ring with a double bond, but the numbering must start from the double bond for accuracy.

Substituent Positioning

Substituent positioning refers to the correct numbering of carbon atoms in a molecule to indicate the location of attached groups. In cyclic compounds, numbering starts from the point of highest priority, such as a double bond or functional group, and proceeds to give the lowest possible numbers to substituents. This concept is essential for correcting names like '6-chlorocyclohexadiene,' where numbering should reflect the actual structure.

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