Question

How to convert ethene to propanoic acid?

Answer 1

Explanation:

We know that cyanide ion attached to a carbon chain hyrolyzes(upon acid hydrolysis) to carboxylic acid and since we need propanoic acid, therefore we will hydrolyze propanenitrile by dilute sulphuric acid with heat and we get propanoic acid: Hope this helped

Answer 2

Ethene + Ozone → HCHO + R-MgX → 1-propanol → Propanoic acid

Step (I)

Ozonolysis :

Ethene reacts with ozone in an inert solvent to produce 2 moles of formaldehyde.

$CH_2=CH_2 + O_3$ → $2HCHO$

Step (II)

Addition of Grignard reagent formaldehyde:

Grignard reagent also known as organomagnesium compound (RMgX) reacts with formaldehyde followed by hyrdrolysis in aqueous acid giving a primary alcohol.

$CH_3CH_2-MgBr ({Grignard}{reagent}) + HCHO( formaldehyde)$ → $CH_3CH_2CH_2-OH (1-propanol)$

Step  (III)

Oxidation of primary alcohol with chromic acid to carboxylic acid :

$CH_3CH_2CH_2-OH + H_2CrO_4 (Chromic acid)$ → $2CH_3CH_2COOH (propanoic acid)$

The product formed is 2 moles of propanoic acid.