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

Cis vs Trans

Organic Chemistry

4. Alkanes and Cycloalkanes

Cis vs Trans

Previous problemNext problem

6:45 minutes

Problem 12c

Textbook Question

Draw the isomers for the following compounds and then name each one:
c. 1,3-pentadiene

Verified step by step guidance

Step 1: Understand the structure of 1,3-pentadiene. The name indicates a five-carbon chain (pent-) with two double bonds (-diene) located at carbons 1 and 3. The molecular formula is C5H8.

Step 2: Draw the structure of the compound. Start with a straight chain of five carbons. Place double bonds between carbons 1 and 2, and between carbons 3 and 4. Add hydrogens to satisfy the valency of each carbon atom.

Step 3: Identify possible isomers. For 1,3-pentadiene, there are two types of isomerism to consider: (a) **Geometric isomerism (cis-trans)** due to the presence of double bonds, and (b) **Structural isomerism** by rearranging the carbon chain or the position of the double bonds.

Step 4: Draw the geometric isomers. For the double bond between carbons 1 and 2, and between carbons 3 and 4, determine the cis (same side) and trans (opposite side) configurations. This will give you the cis-1,3-pentadiene and trans-1,3-pentadiene isomers.

Step 5: Verify and name each isomer. Ensure that each structure adheres to the IUPAC naming rules. For example, the straight-chain isomers with cis and trans configurations are named as cis-1,3-pentadiene and trans-1,3-pentadiene. If structural isomers are formed by rearranging the chain or double bonds, name them accordingly (e.g., 1,4-pentadiene or 2,3-pentadiene).

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.

Isomerism

Isomerism refers to the phenomenon where two or more compounds have the same molecular formula but different structural arrangements or spatial orientations. In organic chemistry, isomers can be classified into structural isomers, which differ in the connectivity of atoms, and stereoisomers, which have the same connectivity but differ in the arrangement of atoms in space. Understanding isomerism is crucial for identifying and naming different forms of a compound.

Dienes

Dienes are organic compounds that contain two double bonds. They can be classified as conjugated, where the double bonds are separated by a single bond, or isolated, where the double bonds are separated by more than one single bond. In the case of 1,3-pentadiene, the double bonds are conjugated, which affects the compound's reactivity and stability. Recognizing the type of diene is essential for drawing its isomers.

Nomenclature

Nomenclature in organic chemistry is the system of naming chemical compounds based on their structure and functional groups. The International Union of Pure and Applied Chemistry (IUPAC) provides rules for naming compounds, which include identifying the longest carbon chain, numbering the carbon atoms to give the lowest possible numbers to the double bonds, and using prefixes and suffixes to indicate the presence of functional groups. Proper nomenclature is vital for accurately communicating the identity of isomers.

Watch next

Master How to name different types of double bonds or rings with a bite sized video explanation from Johnny

Start learning