Purification

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A Perfect Reaction (see all): A purification step would not be required. Perfect World Requiring Purification:

A Nightmare Scenario (see all): Your compound is an oil. No purification method has been reported for its isolation. The crude reaction mixture has three or four isomeric components, all with similar boiling points and Rf values.

Common Rookie Mistakes: Chromatography Distillation

Step by Step (time-sensitive):

  1. Consult the literature. If conditions for successful purification of the compound have been reported, (Crystallization, Distillation, or Chromatography), follow the protocol!
  2. If literature is unhelpful, you must choose a purification method for your compound

    Rules of Thumb (see all):

    For all other situations, use Column Chromatography.

  3. Save a small sample of the crude product mixture in a vial.
  4. Carry out the purification (for specific details, see Crystallization, Distillation, or Chromatography.) Keep everything.
  5. Collect major product components in tared flasks, and assign names to each component. For details, see Record-Keeping.
  6. Compare the components (usually by TLC) with the crude sample in the vial, and with the crude NMR, if any, to ensure that you have isolated the compounds of interest.
  7. Calculate the yield of each component, if the identity of the compounds is known.
  8. If this is the First Time Through, proceed to Analysis III: Characterization.

Tips (see all):

See also: Rookie Mistakes, How to Improve Your Yield, First Time Through, Chromatography Notes, How to Purify by Distillation, How to Handle, How to Work on Small Scale, Reaction Checklist, Troubleshooting the Experiment