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

Previous problemNext problem

3:36 minutes

Problem 9a,b

Textbook Question

Draw the structure for each of the following:
a. 3,3-dimethylcyclopentene
b. 6-bromo-2,3-dimethyl-2-hexene

Verified step by step guidance

Step 1: For part (a), start by identifying the parent structure. The parent structure is 'cyclopentene,' which is a five-membered ring containing one double bond. Draw a cyclopentene ring with one double bond in the structure.

Step 2: Add the substituents to the cyclopentene ring. The name '3,3-dimethyl' indicates that there are two methyl groups attached to the third carbon of the cyclopentene ring. Number the ring carbons such that the double bond gets the lowest possible number (1 and 2). Place the two methyl groups on carbon 3.

Step 3: For part (b), identify the parent structure. The parent structure is '2-hexene,' which is a six-carbon chain with a double bond between carbons 2 and 3. Draw a six-carbon chain and place a double bond between carbons 2 and 3.

Step 4: Add the substituents to the hexene chain. The name '6-bromo' indicates a bromine atom attached to carbon 6, and '2,3-dimethyl' indicates methyl groups attached to carbons 2 and 3. Number the chain such that the double bond gets the lowest possible number (2). Place the bromine atom on carbon 6 and the methyl groups on carbons 2 and 3.

Step 5: Verify the structures for both parts (a) and (b) to ensure that all substituents are correctly placed, the double bonds are in the correct positions, and the structures follow the IUPAC naming conventions.

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.

Cycloalkenes

Cycloalkenes are cyclic hydrocarbons that contain at least one carbon-carbon double bond. In the case of 3,3-dimethylcyclopentene, the structure consists of a five-membered carbon ring with two methyl groups attached to the third carbon. Understanding the geometry and bonding in cycloalkenes is crucial for accurately drawing their structures.

Substituent Positioning

In organic chemistry, the positioning of substituents on a carbon chain or ring is essential for defining the compound's structure and properties. For 6-bromo-2,3-dimethyl-2-hexene, the numbers indicate the specific locations of the bromine and methyl groups on the hexene chain, which is a six-carbon alkene. Correctly identifying these positions is vital for drawing the accurate molecular structure.

Double Bonds and Stereochemistry

Double bonds in alkenes introduce geometric isomerism due to restricted rotation around the bond. In 6-bromo-2,3-dimethyl-2-hexene, the presence of the double bond at the second carbon can lead to cis/trans isomerism, affecting the compound's physical and chemical properties. Recognizing the implications of double bonds and their stereochemistry is important for understanding the overall structure.

Watch next

Master How to name alkenes and alkynes with a bite sized video explanation from Johnny

Start learning

Related Videos

Related Practice

Textbook Question

How many of the following names are correct? Correct the incorrect names.

g. 2-ethyl-2-butene

h. (E)-2-methyl-1-hexene

i. 2-methylcyclopentene

Textbook Question

Which of the following names are correct? Correct those that are not correct.

c. 4-chloro-2-pentyne

d. 2,3-dimethyl-5-octyne

Textbook Question

Draw a condensed structure for each of the following:

i. diethylacetylene

j. di-tert-butylacetylene

Textbook Question

Draw a condensed structure for each of the following:

k. cyclopentylacetylene

l. 5,6-dimethyl-2-heptyne

Textbook Question

Name the following:

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.

e. 2,5-dimethylcyclohexene

Textbook Question

Write structural formulas for the following compounds (includes both old- and new-style names).

(d) cyclohexylacetylene

(e) 5-methyl-3-octyne

(f) trans-3,5-dibromocyclodecyne

Textbook Question

Draw the molecular orbital picture of but-2-yne.

Show more practices