Give the systematic (IUPAC) names of the following alkenes.
(a)
(b)

Verified step by step guidance

Step 1: Identify the longest carbon chain that contains the double bond for each alkene. This will be the parent chain. For compound (a), the longest chain is 5 carbons long, and for compound (b), it is 6 carbons long.

Step 2: Number the carbon atoms in the parent chain starting from the end nearest to the double bond. This ensures the lowest possible numbers for the double bond. For compound (a), the double bond starts at carbon 1, and for compound (b), it starts at carbon 1.

Step 3: Identify and name any substituents attached to the parent chain. In compound (a), there is an isopropyl group attached to carbon 4. In compound (b), there is an ethyl group attached to carbon 4.

Step 4: Combine the names of the substituents with the parent chain name, using the appropriate locants (numbers) to indicate the position of the double bond and substituents. Use the suffix '-ene' to indicate the presence of a double bond.

Step 5: Assemble the full IUPAC name by placing the substituents in alphabetical order, followed by the parent chain name with the locant for the double bond. Ensure that the name reflects the correct structure and positions of the substituents and double bond.

Verified video answer for a similar problem:

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

Video duration:

Was this helpful?

Key Concepts

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

IUPAC Nomenclature

The International Union of Pure and Applied Chemistry (IUPAC) nomenclature is a systematic method for naming organic chemical compounds. It provides rules for naming alkenes based on the longest carbon chain containing the double bond, the position of the double bond, and the presence of substituents. Understanding these rules is essential for accurately identifying and communicating the structure of organic molecules.

Alkenes

Alkenes are hydrocarbons that contain at least one carbon-carbon double bond (C=C). They are unsaturated compounds, meaning they have fewer hydrogen atoms than alkanes with the same number of carbon atoms. The presence of the double bond affects the physical and chemical properties of alkenes, making them more reactive than alkanes, which is crucial for understanding their behavior in chemical reactions.

Substituents and Chain Length

In organic chemistry, substituents are atoms or groups of atoms that replace hydrogen atoms in a hydrocarbon chain. When naming alkenes, it is important to identify the longest continuous carbon chain that includes the double bond and to number the chain to give the lowest possible numbers to the double bond and substituents. This helps in determining the correct IUPAC name and understanding the compound's structure.

Recommended video: