The IUPAC name of CH3CH=C-CHO-CH2-CH3 is:
- 3-Formyl-2-pentene
- 2-Ethylbut-2-enal
- 3-Ethylbut-3-enal
- 2-Ethylcrotonaldehyde
The Correct Option is B
Solution and Explanation
Given compound: CH3CH=C–CHO–CH2CH3
Step 1: Identify the longest carbon chain containing the functional group (–CHO)
The aldehyde group (–CHO) has the highest priority, so numbering starts from the carbon of the –CHO group.
Numbering the chain from the aldehyde end:
1 2 3 4 5 CHO–CH=C–CH2–CH3–CH3
This gives us a five-carbon chain with a double bond between carbon 2 and 3, and a methyl (–CH3) substituent on carbon 2.
Step 2: Name the compound
- Parent chain: butenal (4 carbons with aldehyde and double bond)
- Substituent: ethyl group at position 2
- Double bond at position 2
So, the correct IUPAC name is: 2-Ethylbut-2-enal
Correct answer: Option (B)
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Concepts Used:
Organic Chemistry – Some Basic Principles and Techniques - Reaction Mechanism
SN1 Reaction Mechanism:
SN1 reaction mechanism takes place by following three steps –
- Formation of carbocation
- Attack of nucleophile
- Deprotonation
SN2 Reaction Mechanism:
The SN2 reaction mechanism involves the nucleophilic substitution reaction of the leaving group (which generally consists of halide groups or other electron-withdrawing groups) with a nucleophile in a given organic compound.
Electrophilic Aromatic Substitution Reaction Mechanism:
The mechanism of an electrophilic aromatic substitution reaction contains three main components which are:
- A new sigma bond from C=C is formed during the reaction in the arene nucleophile.
- Due to the breaking of the C-H sigma bond, a proton is removed.
- The C=C bond is reformed and it restores the aromaticity of the compound.
Electrophilic Substitution Reaction Mechanism:
The electrophilic substitution reaction mechanism is composed of three steps, which will be discussed more below.
- Electrophile Generation
- Carbocation Formation
- Proton Removal