A Nightmare Scenario

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  1. Theory suggests that the experiment should work. However, the only precedent you find is either a) in another language b) from 1927 c) has no experimental explanation or d) was published by a group nobody knows about and has never been cited.
  2. It's 9 PM. None of your glassware is clean. You can't decide what scale to run it on and you don't have any of the reagents.
  3. You need to weigh four different reagents: a hygroscopic solid that gets liquidy in the air, 0.05 mg of catalyst, a liquid that clogs syringes and must be distilled immediately before use, and your precious reactant, which is heat and acid sensitive. The reaction must be done at -30oC under argon using a complex glass apparatus, and requires three flasks for successive dropwise addition via cannula.
  4. The reaction takes hours to complete: however, the product is unstable and decomposes slowly under the reaction conditions. Progress cannot be monitored by TLC.
  5. The product mixture is highly reactive and requires dropwise addition of quenching reagent to prevent a volcano-like exothermic eruption.
  6. A number of nightmares are possible at this point:

    For help with these and others, see Troubleshooting: Workup

  7. You can't find your product.
  8. 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.
  9. All of the peaks in your 1H NMR spectrum overlap, the compound is not the one you expected, and you don't know what it is.
  10. It's time to write your thesis. You find that characterization data is missing, and need to repeat some experiments you ran earlier. Your notebook is not very detailed, and you have trouble reproducing the results, and have to work out the experimental conditions and a purification protocol all over again.