Essay on Organic Chem Lab 1
A Diels-Alder reaction is a reaction in which a conjugated diene bonds with an alkane to produce a cyclohexane molecule. This reaction works best with dienes that are electron rich and dienophiles that are electron poor. For this experiment, our dicyclopentadiene is the diene and the maleic acid is our dienophile.
In a Diels-Alder reaction, sigma bonds are formed from pi bonds. For this particular experiment, cyclopentadiene and maleic anhydride react via Diels-Alder in order to produce an endo-bicyclic product: cis-5-norbornene-endo-2,3-dicarboxylic anhydride. This product is a six-membered ring alkene with two sigma bonds.
Materials and Methods
* 3 g maleic anhydride * 5 mL …show more content…
The lab group collected the solid crystals and allowed it to dry in a clam shell apparatus for approximately one week. After the week had passed, the sample was then weighed out to determine how much was collected. The lab group also obtained the melting point temperatures of the final product using a Mel-Temp Melting Point Apparatus. The results are tabulated below.
Final weight of product plus clamshell holding device including product: 10.160 g
Clamshell apparatus weight with filter paper and no product: 5.897 g
Total weight of product: 10.160 g – 5.897 g = 4.263 g of product
Melting points of final product (carried out three times):
- Literature value melting point of cis-norbornene-5,6-endo-dicarboxylic anhydride: 165 C * 160 – 164 C * 161 – 163 C * 161 – 163 C
For this lab experiment, a Diels-Alder reaction was carried out in order to obtain cis-norbornene-5,6-endo-dicarboxylic anhydride. The steps entailed in the lab were followed as precisely as possible. After the experiment and once the product was allowed to dry, a total of 4.26 g of cis-norbornene-5,6-endo-dicarboxylic anhydride was obtained. However, our theoretical value that should have been obtained was 5.02 g.
Our melting point measurements were incredibly precise (see data given under “Results” section) and accurate. Even though we did not obtain as much product as we should have, we can assume that we collected a fairly pure product,