che 326 lab 4

che 326 lab 4 - The Diels-Alder Reaction Experiment 4 xxx...

Info iconThis preview shows pages 1–4. Sign up to view the full content.

View Full Document Right Arrow Icon
The Diels-Alder Reaction Experiment 4 xxx
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
I. PURPOSE: The purpose of the experiment was to perform the multi-step synthesis of cis-nor- bornene-5,6-endo-dicarboxylic anhydride using the Diels-Alder reaction. The success of the re- action was examined for success using melting point and IR spectra analysis. II. RESULTS AND DISCUSSION PART 1. CRACKING DICYCLOPENTADIENE Dicyclopentadiene, initially a white crystalline solid, was heated to 150 (degrees Celsius) to generate .35 grams of cyclopentadiene. The distillate collected as a clear liquid. The first step of the reaction produced a relatively low % yield of 44.6%. At room temperature, cyclopentadiene dimerizes and reverses to become dicyclopentadiene. If the temperature was not kept low enough, some product could have been converted into the unintended starting material. Also, it is possible the seals in the apparatus were not tightly sealed, leaking out some of the cyc- lopentadiene as it vaporized. The limiting reagent was cyclopentadiene in the second step. Be- cause of this, a low percent yield in the first step most likely significantly effected the overall yield in a negative way. Also, conversion back into the starting material could have introduced impurities into the final product, lowering the purity. PART 2: DIELS ALDER REACTION 1 Balanced Chemical Equation
Background image of page 2
Next, cyclopentadiene (the diene) was reacted with the maleic anhydride (the dienophile) and ethyl acetate in hexanes. The mixture gave off heat, indicating a reaction had occurred (lab lec- ture). As the solution cooled to room temperature, crystals began to form, , and continued to form in the ice bath. After filtration and subsequent drying, the product was observed as a white crystalline solid comprised of long platelike crystals. The mass observed was 0.198 grams, indic- ating little success in the synthesis based on efficiency. ANALYSIS:
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 4
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 8

che 326 lab 4 - The Diels-Alder Reaction Experiment 4 xxx...

This preview shows document pages 1 - 4. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online