Diels alder experiment
The yield of product in this experiment was 0.
Diels-Alder Reaction: Experiment Written by Vijay In this experiment, cyclopentadiene and maleic anhydride were reacted in solution to produce a single organic product in crystal form. The low percent yield is resulted because of product loss throughout the experiment.
The second issue, a reaction of cyclopentadiene with another molecule of cyclopentadiene via Diels-Alder mechanism, removes reactant for the desired reaction from solution; this issue can be solved by mixing the reaction solution well, adding cyclopentadiene slowly, and keeping the cyclopentadiene at low temperature to prevent dimerization.
The Week 1 product likely has a higher percent yield figure due to being incompletely dried by pipetting and air drying. Maleic anhydride functions well as a dienophile because of its electron-withdrawing groups and relatively small size.
This issue may be no more than practicing the technique of transferring product and finding the most efficient way of doing so.
Diels alder experiment
If the reaction were thermodynamically controlled, the overall more stable product, the exo product, would be the major product. Once the toluene was added, there was no physical changes. The Week 1 product likely has a higher percent yield figure due to being incompletely dried by pipetting and air drying. Also, being in a ring, the cyclopentadiene is locked into the s-cis conformation that facilitates the Diels-Alder Reaction. The IR spectrum helped encourage this conclusion because 2 peaks were found between cm-1 as shown in figure 2. The stereochemistry can also be found in this experiment. Changing the nonpolar solvent petroleum ether to hexane caused the largest effect on yield based off the Wiki data. The vial was connected to an air condenser and a spin vane.
Also, being in a ring, the cyclopentadiene is locked into the s-cis conformation that facilitates the Diels-Alder Reaction. The change from Sample A to Sample B thus increased the yield by reducing solubility of crystalline product.
Increased solubility of the product indicates a decreased yield, as less of the final product will crystallize. Vacuum filtration appeared to lower yield because a purer product of lesser mass is prepared.
The class data was also obtained and that concluded the experiment.
Diels alder reaction lab report conclusion
Percent yield observed during the first week of experimentation was The first issue could be solved by devising a method of transferring the filtered and dried crystal product from the filtration funnel or beaker in a manner that conserves the product. The mixture was cooled to room temperature then 0. It is important to avoid water in this reaction because the product can be hydrolyzed by water. Prelab and Post Lab Questions: Prelab 1. The cotton balls must be inserted loosely because gas is generated. Later on, the IR was obtained and the spectrum was translated. The boiling point was then determined to be Petroleum ether is composed of a mixture of larger alkanes more than six carbons , whereas hexane is only composed of six-carbon alkanes. Figure 1 The experiment involves 3-sulfolene which is used to generate SO2 gas and 1,3 butadiene as shown in scheme 1 below. The IR and melting point were found at the end of the experiment. The melting point proved that 4-cyclohexene-cis-1,2-dicarboxylic anhydride was obtained during this experiment. Scheme 2 The maleic anhydride and 1,3 butadiene synthesize to create 4- cyclohexene-cis-1,2-dicarboxylic anhydride as shown in scheme 3. Some reasons the product was lost during the experiment is not all the product crystallized in the ice bath.
based on 75 review