23. An Aldol Condensation
Unlike most of the experiments in this course, this experiment is not
done on a microscale. It is still a considerably smaller-scale reaction than
those that were done in organic chemistry laboratories in the past. Note
that there is an error in the equation given for the reaction in Williamson.
See if you can find it.
PRE-EXPERIMENT ASSIGNMENT
Study this chapter in the manual, the lecture notes on the Chemistry
Department web site, and pages 455-456 in Williamson. You will also find it
helpful to study the sections on the aldol reaction and condensation in your
lecture textbook. Do the first parts of your notebook writeup.
A student who has prepared for the Aldol Condensation experiment
should be able to:
1. Define: condensation reaction (this is review). Also, give the reaction for
the condensation of benzaldehyde and acetone to give dibenzalacetone.
2. Give a drawing of, and identify the components from a drawing of, the
apparatus used in the various steps of the reaction and its components.
3. Calculate the theoretical yield and the percent yield for this and similar
experiments given the necessary data, and perform any of the intermediate
calculations required by this process. For this reaction, "necessary data" may
include the volume of a given starting material and its density rather than
simply the mass.
4. Draw the structure given the name, or give the name from the structure,
of the compounds used in the day's experiment, and give the role of each
(reactant, solvent, catalyst, etc.).
5. Identify and explain safety considerations for this experiment.
6. Perform the day's experiments safely and successfully.
Quizzes given after the experiment has been performed may also include:
7. Predict the products of aldol reactions and condensations, and give and
explain the mechanism of such reactions given the balanced equation.
Important topics include enolate anions, electrophiles, and nucleophiles. For
more details see your CHEM 2220 lecture materials.
