The Workup

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A Perfect Reaction (see all): Workup = removal of solvent

A Nightmare Scenario (see all): too many to count. See troubleshooting.

Common Rookie Mistakes: The Workup

Step by Step (time-sensitive):

Follow the instructions in your literature procedure. For an aqueous workup of most organic compounds this will involve:
  1. Diluting the reaction mixture with a solvent for workup (this is the organic layer). Exceptions
  2. Washing the Organic Layer with various aqueous solutions. Some of the byproducts generated during the reaction will be neutralized or removed by dissolving in the aqueous layer. Examples. Ideally, the two layers will be clearly visible. If the result is one cloudy layer, you have an emulsion.
  3. Drying the Organic Layer with one of the drying agents.
  4. Filtering off the drying agent.
  5. Rotoevaporation to remove the solvent.
The residue left is the crude product, ready for diagnosis. Certain types of compounds are more difficult to isolate than others--if your product might be volatile, soluble in water, charged at low or high pH (e.g. an amine or a carboxylic acid), unstable, or possesses stench, see How to Handle.

Rules of Thumb (see all)

The reaction mixture should be diluted to 3-4 times its original volume.

Tips (see all):

See also: Rookie Mistakes, How To Improve Your Yield, Reaction Checklist, Troubleshooting the Experiment

Special Topics:

  1. Workup Formulas for Specific Reagents
  2. Workup Notes
  3. How to Handle
  4. How to Work on Small Scale