How to Separate Optical Isomers

These chiral, or "twin," hands show they are composed and function in the same way, but are oriented differently, like mirror images.

Optical isomers are an oddity in molecular science. Composed of similar agents but in separate orientations, optical isomers are non-superimposable, meaning they cannot be simply oriented in a new direction to match their corresponding "twin." They are classified as chiral elements, from a Greek word meaning "hand." The right and left hands are the best real-world examples of chiral items, meaning they are mirror images, but are not the same. Separating optical isomers requires extensive scientific know-how and tools.

Things You'll Need

• Diastereomeric catalyst/reactants
• Solvents of varying solubility
• Circularly polarized light

Instructions

1. Prepare your optical isomer solution. PatentStorm's "Optical Isomer Separation Method" suggests preparing "single enantiomers by first reacting the racemate with a diastereomeric catalyst/reactant." Boiled down, this means you prep the "playing field" of the compound with a catalyst to allow separation.

2. Separate the diastereomeric compounds by placing the solution in solvents of different solubility. The compound and optical isomers being separated will require different solvents, depending on the compound's composition.

3. Refract circularly polarized light to "enrich the preferred handedness of the enantiomers," PatentStorm suggests. The varying absorption of the light between the differently oriented molecules will separate the enantiomers from the racemate. It does this by using the "momentum transfer" of the light in those molecules absorbing to overcome the diffusion process.

Tips & Warnings

• Other methods involve chromatography columns, which separate directly optical isomers through a stationary phase. An antipode is used instead of a chiral selector, allowing an inverse elution order.

• Separating optical isomers is an extremely complicated procedure involving highly specific scientific education. It's wise to consult a professional to ensure the accuracy of your procedure.

References

• PantentStorm: Optical Isomer Separation Method
• Encyclopedia.com: Isomer Facts
• ChemGuide: Stereoisomerism -- Optical Isomerism
• Sumika Chemical Analysis Service: Chromatography Columns