Question

The compound \(\mathrm{CH}_{3}-\mathrm{C}=\mathrm{CH}_{2}-\mathrm{CH}_{3}\) when treated with \(\mathrm{NaIO}_{4}\) in presence of \(\mathrm{KMnO}_{4}\) gives

Short answer

Answer: The products formed are acetic acid (CH₃-COOH), formic acid (CH₂COOH), sodium manganate (NaMnO₄), potassium iodate (KIO₄), and water (H₂O).

Step-by-step solution

Identify the functional groups

The given compound is CH₃-C≡CH₂-CH₃, which contains an alkyne functional group (C≡C) at the second and third carbon atoms.

Reaction of alkynes with NaIO₄ and KMnO₄

When an alkyne reacts with NaIO₄ in the presence of KMnO₄, the alkyne undergoes oxidative cleavage. In this reaction, the triple bond (C≡C) gets broken, and the two fragments formed are oxidized to obtain carboxylic acid groups (-COOH).

Apply the oxidative cleavage to the given compound

CH₃-C≡CH₂-CH₃ undergoes oxidative cleavage at the alkyne bond, resulting in two fragments: 1. CH₃-COOH (acetic acid or ethanoic acid) 2. CH₂COOH (formic acid or methanoic acid)

Write the final balanced equation

The final balanced equation for the reaction of CH₃-C≡CH₂-CH₃ with NaIO₄ in the presence of KMnO₄ can be written as: CH₃-C≡CH₂-CH₃ + 2 NaIO₄ + 2 KMnO₄ → CH₃-COOH + CH₂COOH + 2 NaMnO₄ + 2 KIO₄ + 2 H₂O

Key concepts

Oxidative Cleavage

Oxidative cleavage is a process where molecules are split into smaller fragments with the help of oxidizing agents. It is a chemical reaction that typically breaks carbon-carbon (C-C) bonds, converting them into carbon-oxygen bonds (like carbonyl groups or carboxylic acids). This process is particularly useful in organic chemistry for transforming complex molecules into simpler, more functional groups.

In the given exercise, oxidative cleavage involves the breaking of the carbon-carbon triple bond in alkynes. The presence of strong oxidizing agents like \( ext{NaIO}_4\) (sodium periodate) and \( ext{KMnO}_4\) (potassium permanganate) helps in this transformation. These reagents work together to facilitate the cleavage of the alkyne into two separate molecules.

Oxidative cleavage is an important reaction because it often leads to the formation of functional groups such as carboxylic acids, which can participate in further chemical synthesis or serve as endpoints in analysis.

Alkyne Reactions

Alkynes are hydrocarbons characterized by a carbon-carbon triple bond (C≡C). This triple bond makes alkynes highly reactive and versatile in organic reactions. The reaction of alkynes with oxidizing agents like \(\text{NaIO}_4\) and \(\text{KMnO}_4\) involves significant transformations.

Here's how the oxidative cleavage of alkynes typically proceeds:

• The triple bond is broken through the addition of oxygen from the oxidizing agents.
• The cleavage results in the formation of two new molecules.
• These molecules are usually oxidized further into carboxylic acids.

In the exercise, the compound \(\text{CH}_3-\text{C}\equiv\text{CH}_2-\text{CH}_3\) undergoes oxidative cleavage, leading to the creation of acetic acid (\(\text{CH}_3\text{COOH}\)) and formic acid (\(\text{CH}_2\text{COOH}\)). This exemplifies alkyne reactions' influence in producing vital organic molecules through oxidative methods.

Carboxylic Acid Formation

Carboxylic acids are a class of organic compounds identified by the presence of at least one carboxyl group (\(-COOH\)). The formation of these compounds is a crucial result of oxidative cleavage reactions.

In oxidative cleavage of alkynes, the triple bond is transformed into two carboxyl groups. Understanding the process:

• Upon oxidative cleavage, electrons from the triple bond are redistributed to form new bonds with oxygen.
• This results in the creation of carboxylic acids, which have a distinct -OH (hydroxyl) group attached to the carbonyl carbon.
• These newly formed carboxylic acids are often more reactive and can engage in various subsequent chemical reactions.

In our specific example, the alkyne compound gives rise to acetic acid and formic acid following oxidative cleavage, illustrating how valuable carboxylic acids are in organic chemistry for forming new compounds and materials.