To convert acetone (propanone) to propanal, you can use a two-step process involving reduction and oxidation reactions. Here's a general outline of the process:
1. Reduction of Acetone to Isopropanol:
First, you need to reduce acetone to isopropanol (2-propanol) using a reducing agent. Common reducing agents for this step include sodium borohydride (NaBH₄) or lithium aluminum hydride (LiAlH₄).
Reaction conditions:
- Acetone + NaBH₄ (or LiAlH₄) → Isopropanol
- Solvent: usually an alcohol (e.g., methanol or ethanol) or an ether (e.g., THF)
- Temperature: room temperature or slightly above
2. Oxidation of Isopropanol to Propanal:
Next, oxidize isopropanol to propanal using an appropriate oxidizing agent. A common oxidizing agent for this step is pyridinium chlorochromate (PCC), which selectively oxidizes primary alcohols to aldehydes without over-oxidizing to carboxylic acids.
Reaction conditions:
- Isopropanol + PCC → Propanal
- Solvent: an aprotic polar solvent (e.g., dichloromethane)
- Temperature: room temperature
- Avoid strong oxidizing agents like potassium permanganate (KMnO₄) or chromium trioxide (CrO₃) because they can over-oxidize the isopropanol to propionic acid.