Start with an introductory statement that describes the reaction s done and the percent yield obtained and lists the techniques used to characterize the product. 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.
The reaction has gone to completion because the melting point of the observed product is well above the melting points of the reactants and solvents involved; if the reaction had not gone to completion, the melting process would have begun much earlier due to maleic anhydride melting.
For the enantiomer, just switch R to S and S to R. Write the mechanism with curved arrows to show electron movement for the Diels-Alder reaction and the intramolecular nucleophilic acyl substitution. 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.
Both the anthracene and maleic anhydride dissolved immediately in xylene to give a slightly yellow solution. Lewis acid catalysis also enables Diels—Alder reactions to proceed at low temperatures, i.
This reaction was carried out using standard reflux conditions. Regardless of which situation pertains, the HOMO and LUMO of the components are in phase and a bonding interaction results as can be seen in the diagram below. You can hand-draw structures in ink. Spectra of starting materials are available on the Vista site.
The change from Sample A to Sample B thus increased the yield by reducing solubility of crystalline product. Imidazolinium salts as catalysts for the aza-Diels-Alder reaction V. The Diels-Alder adduct, 9,Dihydro-9,ethanoanthracene,dicarboxylic anhydride, was successfully synthesized from anthracene and maleic anhydride.
Sample B was purified by vacuum filtration, but also included an additional 0. Danz, Synthesis, You should also analyze any NMR spectra that you have from the reaction if applicable.
The crystals were a pale yellow color, with an irregular, powdery shape. Percent yield observed during the first week of experimentation was Pairing these two coefficients gives the "ortho" product as seen in case 1 in the figure below.
Lewis acid catalysis also enables Diels—Alder reactions to proceed at low temperatures, i. For the second week of experimentation, the percent yields observed were The alkene carbons, C-2 and C-3, exhibited a peak at Petroleum ether is composed of a mixture of larger alkanes more than six carbonswhereas hexane is only composed of six-carbon alkanes.
The Diels-Alder reaction is a concerted mechanism. A cyclic 1. an adduct formed from a Diels-Alder reaction from a diene in the s-trans conformation would have much steric strain and therefore is much less likely than one produced from a 5/5(2).
Diels-Alder is a concerted reaction between a diene and a dienophile that results in a cyclohexene.1 The reaction can involved molecules with a large variety of substituents, so long as there is a diene with high electron density and a dienophile with low electron density.5/5(3).
lower the energy of the transition state of Diels-Alder reactions. Overall, then, for anthracene it is sufficient to use a high boiling solvent such as xylene to drive the reaction forward.
Cyclopentadiene is a good diene for the Diels-Alder reaction because of its substitution and its locked s-cis conformation. Due to cyclopentadiene being substituted, the diene can draw on the electron density of the methylene in between the diene.
The Diels-Alder reaction is a member of a larger class of pericyclic reactions. These are reactions For your report: Calculate your percent yield. Discuss the results of your percent yield, your melting point and IR spectrum.
Predict the 1 H-NMR spectrum for the product. Diels Alder Lab Report. or any similar topic specifically for you. Do Not Waste This particular Diels-Alder reaction exploits an interesting phenomenon.
Although aromatic compounds do not normally participate in Diels-Alder reactions, the central ring in anthracene is reactive as a diene. Since all three rings of anthracene can not.Diels alder reaction lab report