Organic conversion

Ethanol to propanenitrile

2 steps: substitution, then substitution

Class 12, Chapter 6 Haloalkanes and Haloarenes

EthanolCH₃CH₂OHAlcohol
Step 1
SOCl₂
i
Thionyl chloride gives the pure alkyl chloride because SO₂ and HCl leave as gases.
Also written: HCl, anhydrous ZnCl₂
ChloroethaneCH₃CH₂ClHaloalkane
Step 2
KCN (alcoholic)
i
KCN attacks through carbon, adding one carbon.
PropanenitrileCH₃CH₂CNNitrile

Alternative routes (4)

Ethanol → Bromoethane → Propanenitrile
1. Ethanol to bromoethane: red P + Br₂ (PBr₃).
2. Bromoethane to propanenitrile: KCN (alcoholic).
Ethanol → Ethene → Bromoethane → Propanenitrile
1. Ethanol to ethene: conc. H₂SO₄, 443 K.
2. Ethene to bromoethane: HBr.
3. Bromoethane to propanenitrile: KCN (alcoholic).
Ethanol → Ethene → Chloroethane → Propanenitrile
1. Ethanol to ethene: conc. H₂SO₄, 443 K.
2. Ethene to chloroethane: HCl.
3. Chloroethane to propanenitrile: KCN (alcoholic).
Ethanol → Ethene → Ethane → Chloroethane → Propanenitrile
1. Ethanol to ethene: conc. H₂SO₄, 443 K.
2. Ethene to ethane: H₂, Ni (or Pt, Pd).
3. Ethane to chloroethane: Cl₂, UV light.
4. Chloroethane to propanenitrile: KCN (alcoholic).

Why these reagents

Reagent and reason, step by step

Step 1: Ethanol to chloroethane: SOCl₂ Thionyl chloride gives the pure alkyl chloride because SO₂ and HCl leave as gases.
Step 2: Chloroethane to propanenitrile: KCN (alcoholic) KCN attacks through carbon, adding one carbon.

Questions

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

2 steps: Ethanol, then chloroethane, then propanenitrile.

Which named reaction is used to convert ethanol to propanenitrile?

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

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

Ethanol to chloroethane: SOCl₂. Thionyl chloride gives the pure alkyl chloride because SO₂ and HCl leave as gases.