Reaction of 9-Anthraldehyde with Maleic Anhydride via the Diels-Alder Reaction
Sam P. Le
The purpose of this experiment was to demonstrate the
utility of the Diels-Alder reaction by
reacting 9-anthraldehyde with maleic anhydride to form a9-anthraldehyde-maleic anhydride adduct. The 9-anthraldehyde-maleic anhydride adduct was characterized by melting point determination, infrared (IR) spectroscopy, UV-Vis absorption spectroscopy, as well as lH NMR spectroscopy. Reagent Table
Molecular weight (s/mol)
9-anthraldehyde (9anthracenec arboxaldehyde)
Melting point ("C)
Boiling point ("C)
Miscellaneous information 52-s4
Corrosive, toxic Flammable
Heavy mineral oil
Structures, Chemical equations, and Mechanisms a CI4,O
o aleia- a^l^,X|riL
Sample lab report for Experiment
in Palleros (pp. 39S-a00)
The experiment was conducted according to the procedure describedin Palleros, Experimental
Organic Chemistry . The only modification to the published procedure was the addition of a sand bath to improve heating during reflux.
Data and Observations
Amount of maleic anhydride used: 350 mg
Amount of 9-anthraldehyde used: 250 mg
Weight of 9-anthraldehyde-maleic anhydride adduct (crude): 325 mg
Appearance of adduct (crude): white, powdery solid
Amount of crude product used for recrystallization: 150 mg
Amount of recrystallized adduct recovered: 92 mg
Appearance of recrystallized adduct: colorless needles
MP of recrystallized adduct: 234-239'C
IR and UV-Vis spectra of 9-anthraldehyde are attached
IR, UV-Vis, and rH NMR spectra of recrystallizedg-anthraldehyde-maleic anhydride are attached as Figure 3 and 4 respectively.
Calculation of theoretical yield attached as Figure 5.
(actual yield / theoretical yield)
(325 mg / 368 mg) x 100
Percent recovery of adduct in
recrystallization: (mass recovered / mass of crude used) x l00Yo
Sample lab report for Experiment 19A.1 in Palleros (pp. 398-a00)
In this experiment, the usefulness of the Diels-Alder reaction in organic synthesis was demonstrated by the reaction of 9-anthraldehyde with maleic anhydride to form a 9anthraldehyde-maleic anhydride adduct.
The Diels-Alder reaction is an example of a cycloaddition reaction and is an important reaction
in organic synthesis. The usefulness of the Diels-Alder reaction arises from the fact that two carbon-carbon bonds can be formed in a single step. Consequently, large and complex molecules can be achieved in an efficient manner. The Diels-Alder reaction is also referred to as a [4+2]
cycloaddition reaction because it involves the reaction of a conjugated diene, which contains 4 zr electrons, and a dienophile, which contains 2 n electrons. When a conjugated diene reacts with a
dienophile, a 6-membered ring product, known as an adduct, is formed .
In a Diels-Alder reaction, the bonds are broken and formed simultaneously and, therefore, is a concerted reaction. While the Diels-Alder reaction proceeds readily,
it is also
reaction. At high temperatures, the Diels-Alder adduct decomposes into a conjugated diene and a dienophile . Interestingly, the conjugated diene and dienophile formed in a retro-Diels-Alder
reaction are not necessarily the original starting diene and dienophile in some cases .