1. Which kinds of alcohols produce aldehydes when oxidized?
2. Which kinds of alcohols produce ketones when oxidized?
3. Which kinds of alcohols can be oxidized to carboxylic acids?
4. Is cyclohexanol a primary or secondary alcohol? What about phenol?
5. What is the product of oxidation of cyclohexanol? Draw its structure.
6. Under ordinary conditions, all aldehydes and ketones are in their keto forms. However, they can undergo a conversion to the corresponding enol form. These two forms are actually in equilibrium with each other, but keto form is usually more stable. Keto-enol interconversion is the most common form of tautomerism. Write the equilibrium of this reaction for acetaldehyde.
7. In the case of acetaldehyde, the keto form predominates (99%) because the C=O bond is much stronger than the C=C bond. However, 2,4- pentadione is 80% the enol form at equilibrium as a result of an intramolecular hydrogen bond. Write the structure of 2,4-pentadione and that of the enol form with the hydrogen bond. Draw the hydrogen bond as a dotted or dashed line.