Question

Using your roadmap as a guide, show how to convert cyclohexane into hexanedial. Show all reagents and all molecules synthesized along the way. O=CCCCCC=O Cyclohexane Hexanedial

Short answer

Question: Describe the series of reactions required to convert cyclohexane to hexanedial. Answer: To convert cyclohexane to hexanedial, follow these steps: 1. Oxidize cyclohexane to cyclohexanol using potassium permanganate (KMnO4) and water (H2O). 2. Oxidize cyclohexanol to cyclohexanone using Jones reagent, a mixture of chromium trioxide (CrO3) and sulfuric acid (H2SO4) in acetone. 3. Perform a Baeyer-Villiger Oxidation on cyclohexanone using peroxyacetic acid (CH3CO3H) to obtain ε-caprolactone. 4. Hydrolyze ε-Caprolactone using water (H2O) and a catalytic amount of base like lithium hydroxide (LiOH) or potassium hydroxide (KOH) to produce 6-hydroxyhexanoic acid. 5. Oxidize 6-hydroxyhexanoic acid to hexanedial using pyridinium chlorochromate (PCC).

Step-by-step solution

Oxidation of Cyclohexane to Cyclohexanol

Using potassium permanganate (KMnO4) and water (H2O) as the solvent, oxidize cyclohexane to cyclohexanol. This reaction occurs under mild conditions and gives cyclohexanol as the main product. Cyclohexane + KMnO4 + H2O -> Cyclohexanol + MnO2 + KOH

Oxidation of Cyclohexanol to Cyclohexanone

Perform another oxidation reaction using Jones reagent, which is a mixture of chromium trioxide (CrO3) and sulfuric acid (H2SO4) in acetone. This reaction will convert cyclohexanol to cyclohexanone. Cyclohexanol + Jones Reagent -> Cyclohexanone + Cr(SO4)3 + H2O

Baeyer-Villiger Oxidation of Cyclohexanone to ε-Caprolactone

In this step, use peroxyacetic acid (CH3CO3H) as a reagent for Baeyer-Villiger Oxidation, which will convert cyclohexanone to ε-caprolactone. Cyclohexanone + CH3CO3H -> ε-Caprolactone + CH3COOH

Hydrolysis of ε-Caprolactone to 6-Hydroxyhexanoic acid

Next, hydrolyze ε-Caprolactone by using water (H2O) and a catalytic amount of base like lithium hydroxide (LiOH) or potassium hydroxide (KOH) to obtain 6-hydroxyhexanoic acid. ε-Caprolactone + H2O + Base -> 6-Hydroxyhexanoic acid

Oxidation of 6-Hydroxyhexanoic acid to Hexanedial

For the final step, oxidize 6-hydroxyhexanoic acid to hexanedial using pyridinium chlorochromate (PCC) as an oxidizing agent. Due to the presence of the hydroxyl group, the oxidation will occur on both ends, converting the molecule into hexanedial. 6-Hydroxyhexanoic acid + PCC -> Hexanedial + PCC's reaction products

Key concepts

Oxidation Reactions

In organic chemistry, oxidation reactions play a vital role in transforming molecules by altering their structure. Oxidation involves the increase of oxygen or the decrease of hydrogen within a compound. This transformation often utilizes oxidizing agents such as potassium permanganate or chromium trioxide.

Oxidation steps can vary in their complexity:

• First, the oxidation of cyclohexane with potassium permanganate converts it to cyclohexanol. This involves inserting an oxygen atom resulting from the mixture of KMnO4 and water.
• Then, the cyclohexanol undergoes oxidation with Jones reagent, consisting of chromium trioxide and sulfuric acid, forming cyclohexanone.
• Finally, 6-hydroxyhexanoic acid undergoes oxidation with pyridinium chlorochromate (PCC), leading to the formation of hexanedial.

Real-life applications involve converting fossil fuels into valuable compounds or in pharmaceutical synthesis. Through oxidation, chemists can strategically introduce oxygen elements to transform the chemical properties and reactivity of organic compounds.

Cyclohexane Derivatives

Cyclohexane derivatives are a group of compounds that have cyclohexane as their backbone, possessing significant importance in synthetic chemistry. Cyclohexane itself is a simple hydrocarbon, but when functionalized, it becomes a platform for producing more complex molecules.

Transformation of cyclohexane involves:

• Oxidation to cyclohexanol, which introduces a hydroxyl group, thus creating the first derivative.
• Further oxidation then transforms cyclohexanol into cyclohexanone, introducing a carbonyl group.
• Cyclohexanone serves as a critical intermediate that can undergo Baeyer-Villiger oxidation, producing derivatives like ε-caprolactone.

These derivatives are useful in various sectors, including polymers, pharmaceuticals, and fragrances. Understanding how to manipulate cyclohexane through oxidation sets a foundation for synthesizing a range of valuable products.

Baeyer-Villiger Oxidation

The Baeyer-Villiger oxidation is a fascinating reaction in organic chemistry that extends the range of attainable products from carbonyl compounds. It introduces an oxygen atom across the carbon-carbon bond adjacent to a carbonyl group to form an ester or lactone.

To achieve this conversion:

• Cyclohexanone undergoes treatment with peroxyacetic acid (CH3CO3H), acting as the oxidizing agent. This transforms the compound into ε-caprolactone, a cyclic ester.
• Peroxy acids like peroxyacetic acid are crucial in providing the necessary oxygen atom at the precise location within the molecule.

This reaction is instrumental in producing lactones, which are important in the synthesis of polymers and raw material compounds. By enabling the insertion of an oxygen atom into the carbonyl adjacent position, the Baeyer-Villiger oxidation is a unique tool for expanding the structural complexity of organic molecules.