Question

Ozonolysis-reduction of an unknown alkene gives equal amounts of CH3CH2CHO and CH3CH2CH2CHO. Name the unknown alkene.

Answer 1

The unknown alkene that would yield equal amounts of propionaldehyde and butyraldehyde upon ozonolysis-reduction is pent-3-ene, which has a symmetrical structure with the double bond at the central position of the carbon chain.

Step-by-step explanation:

When an unknown alkene undergoes ozonolysis-reduction and produces equal amounts of CH3CH2CHO (propionaldehyde) and CH3CH2CH2CHO (butyraldehyde), it suggests that the alkene had a symmetrical structure. Ozonolysis of alkenes cleaves the double bond, splitting the alkene into carbonyl compounds. The reductive workup then produces aldehydes or ketones, depending on the substituents attached to the double bond.

Since the alkene produces two different aldehydes with the same carbon backbone length, we can infer that the double bond was centrally located within the carbon chain. Using this information, we can deduce that the initial alkene is pent-3-ene, which upon ozonolysis, would yield the two observed aldehydes in equal amounts.

The reaction mechanism could be described as follows:

1. The ozonolysis of pent-3-ene splits the double bond at the 3rd position.
2. Reductive workup converts the resulting ozonides into the aldehydes CH3CH2CHO and CH3CH2CH2CHO.