Diels-Alder Reaction

Equipment

Reagents

Presentation

1. Add 1 mL of N-PTD solution to each of the three test tubes. The first tube is only used to show the color of the N-PTD before reaction with a diene.
2. To the second test tube add 15 drops of anthracene solution.
3. To the third test tube add 15 drops of furan solution.
4. Draw the solutions in test tubes 2 and 3 into a pipet in order to mix the contents.

Hazards

Discussion

The Diels-Alder reaction was discovered in 1928 by German chemists Otto Diels and Kurt Alder, who received the Nobel Prize in chemistry in 1950 for their work towards understanding this 4+2 cycloaddition. The Diels-Alder reaction continues to be a widely used reaction in modern organic synthesis because in one step two carbon-carbon bonds are made in a stereoselective way. In the Diels-Alder reaction, an alkene or an alkyne react with a conjugated diene to form an unsaturated six-membered ring. For this demonstration, a colorless diene (furan (1) or anthracene (2)) is reacted with a red dieneophile (4-phenyl-1,2,3-triazolin-3,5-dione (N-PTD) (3)) and a colorless adduct is formed.



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The idea for this demonstration and some of its procedures were taken from a website originating from the University of Regensburg¹.

References

1. http://www.uni-regensburg.de/Fakultaeten/nat_Fak_IV/Organische_Chemie/Didaktik/Keusch/p2_cyclo_add-e.htm (as seen on June 20, 2003)