Week 16: Aldehydes & Ketones
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What are they?: Organic compounds which contain a carbonyl group.
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In ketones, C must be attached to the carbonyl group.
In aldehydes, at least one H is attached to the carbonyl group.
Naming them ✅
Ketones: named with the suffix “one”. Multiple ketone groups …..dione
Aldehydes;named with the suffix “al”.Multiple aldehyde groups: …..dial
HAS HIGHER PRIORITY THAN KETONE
Step 1: Find the longest parent chain that contains the –CHO group
Step 2: Start numbering the carbon from the end that is nearer to the -COH group
Step 3: Identify the other substituents & positions. Arrange in alphabetical order
Step 1: Find the longest parent chain that contains the –C=O group
Step 2: Start numbering the carbon from the end that is nearer to the –C=O group
Step 3: Identify the other substituents & positions. Arrange in alphabetical order
Physical Structure & Properties
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Boiling point: lower boiling point as compared to previous few functional groups.
Can only form dipole-dipole interactions amongst themselves
Making them ✅
Oxidation of alcohols
What / How do they react ?
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Aldehydes: Oxidation to carboxylic acids
Under basic condition: Tollens’ reagent (AgNO3 + aqueous NH3 + NaOH)
Under acidic condition: Chromium trioxide (CrO3)
Both: Nucleophilic Addition Reactions
Case #1: Hydrides (H:-) as Nucleophiles
Case #2: Grignard reagents (R:-) as Nucleophiles
