Fundamentals of Organic ChemistryChemistryAmines
Ephedrine is a secondary amine widely used in cold and allergy medications. It is typically formulated as its hydrochloride salt rather than as the free amine because:
Options
- Athe free amine is unstable and easily oxidized by air, while the salt is resistant to atmospheric oxidation.
- Bthe free amine is insoluble in water, while the salt is soluble in water.
- Call of the above reasons are correct.
- Dthe free amine has an unpleasant smell, while its salt is odourless.
Correct answer
C. all of the above reasons are correct.
Step-by-step solution
Amines are typically formulated as their hydrochloride salts in pharmaceutical preparations for several reasons. First, free amines are often susceptible to oxidation by atmospheric oxygen, making them unstable over time, whereas their protonated salts are highly resistant to such oxidation. Second, free amines generally have poor solubility in water, which hinders their absorption and formulation in aqueous media. Converting them into ionic hydrochloride salts significantly increases their water solubility. Third,