Which method can be used to separate enantiomers by forming diastereomeric salts?

Which method can be used to separate enantiomers by forming diastereomeric salts?

• A. Distillation
• B. Crystallization with a chiral reagent
• C. Simple filtration
• D. Sublimation

Answer: (B)

Separating enantiomers often relies on converting them into diastereomers, which have different physical properties. Enantiomers on their own have nearly identical boiling points, solubilities, and melting points, so they can’t be split by simple methods like distillation, filtration, or sublimation. By reacting each enantiomer with a chiral reagent, you form diastereomeric salts that differ in solubility. Crystallizing one diastereomeric salt from a solution lets you collect that enantiomer in a pure form (as its salt) while the other remains dissolved; you can then liberate the free enantiomer by removing the resolving agent. This approach—crystallization with a chiral reagent—provides a practical route to separate enantiomers via diastereomer formation.

Separating enantiomers often relies on converting them into diastereomers, which have different physical properties. Enantiomers on their own have nearly identical boiling points, solubilities, and melting points, so they can’t be split by simple methods like distillation, filtration, or sublimation. By reacting each enantiomer with a chiral reagent, you form diastereomeric salts that differ in solubility. Crystallizing one diastereomeric salt from a solution lets you collect that enantiomer in a pure form (as its salt) while the other remains dissolved; you can then liberate the free enantiomer by removing the resolving agent. This approach—crystallization with a chiral reagent—provides a practical route to separate enantiomers via diastereomer formation.