Oxidizing Alcohols Lecture Notes

Introduction

• Topics Covered:
  • Classifying alcohols
  • Oxidizing agents
  • Structures and names of oxidized alcohol compounds
• Alcohols Discussed:
  • Butan-1-ol
  • Butan-2-ol
  • 2-Methylpropan-2-ol

Classifying Alcohols

• Primary Alcohols:
  • Example: Butan-1-ol
  • OH group attached to a carbon attached to only one other carbon
  • Represented with a degree sign
• Secondary Alcohols:
  • Example: Butan-2-ol
  • OH group attached to a carbon attached to two other carbons
• Tertiary Alcohols:
  • Example: 2-Methylpropan-2-ol
  • OH group attached to a carbon attached to three other carbons

Oxidizing Agents

• Acidified Potassium Dichromate
  • Colour change from orange to green/blue upon successful oxidation
• Copper(II) Oxide
  • Black color; reduces to red-brown copper metal if oxidation occurs

Oxidation of Alcohols

Primary Alcohols

• Process:
  • Primary alcohol → Aldehyde → Carboxylic Acid
  • Involves loss of hydrogen atoms and increase in oxygen
• Example:
  • Butan-1-ol can be oxidized to form a carboxylic acid
  • Oxygen to hydrogen ratio increases during oxidation

Secondary Alcohols

• Process:
  • Secondary alcohol → Ketone
  • No further oxidation as no hydrogen remains to form more oxygen bonds
• Example: Butan-2-ol oxidizes to form a ketone

Tertiary Alcohols

• Process:
  • No oxidation occurs
  • No hydrogen available for oxidation

Identifying Aldehydes and Ketones

• Tests to Differentiate:
  • Acidified Dichromate: Turns blue-green with aldehydes
  • Fehling's or Benedict's Solution: Blue to orange-red with aldehydes
  • Tollens' Reagent: Forms a silver mirror with aldehydes

Naming Aldehydes and Ketones

• Aldehydes:
  • Longest chain with carbonyl
  • Ends in -al
• Ketones:
  • Longest chain with carbonyl
  • Ends in -one

Examples

• Naming:
  • 4-methylhexan-3-one
  • 3,3-dimethylbutanal
• Drawing:
  • Pentan-3-one with methyl group on C2
  • Butanal with a methyl group on C3

Conclusion

• Further Learning:
  • Check out related videos on naming branched alcohols
• Engagement:
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