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The Formation of Diels-Alder Reactions

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The Formation of Diels-Alder Reactions
The Formation of Diels-Alder Reactions The Diels-Alder reactions consist of a reversible dienophile and diene all in a one-step reaction initiated by head. These reactions form a six membered ring with at least one pi bond and two sigma bonds, making the reaction exothermic. The goal of the first part of these experiments is to make products that have a greater aromatic stabilization. In 1928, Otto Paul Hermann Diels and Kurt Alder first documented this type of reaction, hence the name Diels-Alder reactions. Their reaction is one of the more useful reactions done in chemistry because it does not require very much energy in order to make the cyclohexene ring and the result can create four stereo centers, making it compatible for a variety of functional groups which still has double bonds in the products.
Dimethyl Tetraphenylphthalate. Tetraphenylcyclopentadienone (0.100g), dimethyl acetylene-dicarboxylate (0.1mL), and nitrobenzene (1mL) was placed into a reaction tube with a boiling stick. The reaction was heated until the purple solution turns tan and refluxed. Ethanol(3mL) was stirred in after the solution was warm, and placed in ice. The solid was vacuum filtered, washed with ethanol, dried and weighed.
Hexaphenylbenzene. Tetraphenylcyclopentadienone (0.100g) and diphenylacetylene (500mg) was placed in a reaction tube and loosely capped. The solid was heated to reflux with a sad bath until the solid turned a brown color. The tube was shaken gently to bring about white solids at the bottom of the reaction tube. Diphenyl ether(2mL) was added and heated until the solid dissolved. The reaction tube was cooled again and had toluene(2mL) added then placed in ice. The product was vacuum filtered, washed with toluene, dried, and weighed.
Tetraphenylnaphthalene. Tetraphenylcyclopentadienone(0.500g), glyme(3mL), and a boiling chip was added to a reaction tube. Isoamyl nitrite(0.35mL) was added via syringe to reaction tube and heated to reflux for 2-5 minutes.

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