Aldol condensation of acetophenone with anisaldehyde
Thobby108
orgo2lab-exp9.Aldolcondensation-bb-s20201.ppt
CHEM 234
Procedure
Into a 25 or 50 mL Erlenmeyer flask are placed 10 mmole of acetophenone, 10 mmole of anisaldehyde, 5 mL of 95% ethanol, and 8 mL of 10% sodium hydroxide solution. The mixture is stirred for 30 minutes during which
time a solid forms. If an oil forms, it can be induced to crystallize by cooling the reaction mixture and scratching the flask with a glass rod extending into the oil. The reaction mixture is cooled and suction filtered using a Büchner funnel. The weight of the crude product is recorded in your laboratory notebook and a percent yield calculated for the unpurified product. The crude solid is recrystallized from a small amount ( up to 10 mL) of 95% ethanol. To carry out the recrystallization, the crude product is dissolved in a minimum amount of boiling hot ethanol and then allowed to slowly cool to room temperature. After crystals have formed at room temperature, the flask is cooled in ice bath. The purified crystalline product is collected by filtration.
The weight of the recrystallized product is determined and the percent yield is calculated.
Take IR of your product.
Experiment 9. Aldol condensation of acetophenone with anisaldehyde
Discussions:
- How would you confirm this reaction using IR spectroscopy?
- Discuss a carbonyl peak of trans-p-anisalacetophenone in IR spectrum compared with the standard peak position (~1700 cm-1).
3. Draw the reaction mechanism of the following Aldol condensation.
4. In the above reaction, how would you change the reaction scheme if you want to synthesize benzalacetone (C6H5CH=CHCOCH3) and benzalacetophenone (C6H5CH=CHCOC6H5)?
References
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