Spectra of starting materials are available on the Vista site. Due to this fact, any unreacted starting materials would remain soluble throughout the recrystallization process.
Since all three rings of anthracene can not simultaneously have benzenoid character Figure 1the electrons in the pi system of the central ring react more like those of a standard diene.
Resonance structures of anthracene. The purity of the crystals was improved as seen in the melting point for the recrystallized product. This particular Diels-Alder reaction exploits an interesting phenomenon. The purified crystals that were collected from the recrystallization were a faint off-white color, with a regular, shiny plate-like shape.
The reaction of the central ring in anthracene allows for the formation of two, independent benzene rings, as seen in the mechanism outlined in Figure 2. Conclusions Write a brief paragraph that summarizes your results.
This reaction was carried out using standard reflux conditions. We will write a custom essay sample on Diels Alder Lab Report or any similar topic specifically for you Do Not Waste HIRE WRITER Crystal formation occurred almost immediately after removing the round-bottomed flask from the heating mantle, with even more crystals forming during the time the flask was in the ice bath.
As the reflux was conducted, the reaction mixture appeared to darken a bit in color, and after 30 minutes, it was a distinct yellow color. Although aromatic compounds do not normally participate in Diels-Alder reactions, the central ring in anthracene is reactive as a diene.
Additionally, the Diels-Alder product is soluble in boiling xylene, but insoluble in cool xylene. You can hand-draw structures in ink. All figures should have captions. The crystals were a pale yellow color, with an irregular, powdery shape. This makes for an ideal recrystallization solvent.
Xylene is an excellent solvent for both anthracene and maleic anhydride, as evidenced by their complete solubility in the early part of the synthesis. Chemistry Be sure to address any questions posed in the lab procedure as well as any additional questions that your TA wants you to answer.
You should also analyze any NMR spectra that you have from the reaction if applicable.
The Diels-Alder adduct, 9,Dihydro-9,ethanoanthracene,dicarboxylic anhydride, was successfully synthesized from anthracene and maleic anhydride. The crude material was recrystallized from boiling xylene.
Both the anthracene and maleic anhydride dissolved immediately in xylene to give a slightly yellow solution. Mechanism of the Diels-Alder reaction.Introduction: In this lab, a Diels-Alder reaction formed a six-membered ring of cyclohexene-1,2-dicarboxylic anhydride when a conjugated diene, Butadiene sulfone, was reacted with a dienophile, Maleic Anhydride%(17).
Lab #4 May 26, Diels Alder Reaction Introduction: Diels Alder Reaction is the reaction of a diene with a species capable of reacting with the diene, the dienophile.
A diene is a hydrocarbon that contains two carbon double bonds, while a dienophile is an electron-deficient alkene. Minor lab report – include the following: All “minor” components described in the “How to write a strong lab report” general guidelines Discuss the theory of stereochemistry applied to this experiment.
In this experiment a Diels-Alder reaction was carried out between 1,3-cyclohexadiene and maleic anhydride to form a new bicyclic ring adduct, Biclyclooctaene 2,3- dicarboxylic acid anhydride.
Diels-Alder Reaction 95 Diels-Alder Reaction General Diels-Alder Reaction: A conjugated “diene” reacts with a “dienophile” to produce a Standard Synthesis Laboratory Report Format: The following layout is standard for a “synthesis reaction” report. Provide the parts and information in the sequence specified.
Pre-Laboratory Questions–EXP 2 Name: Due before lab begins. Answer in space provided. 1. Define the terms diene and dienophile as they apply to the Diels-Alder .Download