Organic conversion

Ethanol to ethanal

1 step: oxidation

Class 12, Chapter 7 Alcohols, Phenols and Ethers

Alternative routes (4)

Ethanol → Ethanoic acid → Ethanoyl chloride → Ethanal
1. Ethanol to ethanoic acid: KMnO₄, KOH, heat; then H₃O⁺.
2. Ethanoic acid to ethanoyl chloride: SOCl₂.
3. Ethanoyl chloride to ethanal: H₂, Pd/BaSO₄.
Ethanol → Ethanoic acid → Ethyl ethanoate → Ethanal
1. Ethanol to ethanoic acid: KMnO₄, KOH, heat; then H₃O⁺.
2. Ethanoic acid to ethyl ethanoate: CH₃CH₂OH, conc. H₂SO₄ (catalyst), heat.
3. Ethyl ethanoate to ethanal: (i) DIBAL-H (ii) H₂O.
Ethanol → Ethene → 1,2-Dibromoethane → Ethyne → Ethanal
1. Ethanol to ethene: conc. H₂SO₄, 443 K.
2. Ethene to 1,2-dibromoethane: Br₂ in CCl₄.
3. 1,2-Dibromoethane to ethyne: (i) alc. KOH, heat (ii) NaNH₂.
4. Ethyne to ethanal: H₂O, dilute H₂SO₄, HgSO₄, 333 K.
Ethanol → Ethanoic acid → Ethanamide → Ethanenitrile → Ethanal
1. Ethanol to ethanoic acid: KMnO₄, KOH, heat; then H₃O⁺.
2. Ethanoic acid to ethanamide: NH₃, then heat.
3. Ethanamide to ethanenitrile: P₂O₅, heat.
4. Ethanenitrile to ethanal: (i) SnCl₂ + HCl (ii) H₃O⁺.

Why these reagents

Reagent and reason, step by step

Step 1: Ethanol to ethanal: PCC Pyridinium chlorochromate stops at the aldehyde; stronger oxidants go on to the acid.

Questions

How many steps does it take to convert ethanol to ethanal?

1 step: Ethanol, then ethanal.

Which named reaction is used to convert ethanol to ethanal?

None of the steps has a name. They are oxidation, so write the reagent and the condition for each step.

What is the reagent for step 1 of ethanol to ethanal?

Ethanol to ethanal: PCC. Pyridinium chlorochromate stops at the aldehyde; stronger oxidants go on to the acid.