Saturday, February 23, 2019
Diels-Alder reaction Essay
PurposeIn this prove a Diels-Alder reaction was used to form the convergences. Cyclopentadiene and maleic anhydride were reacted together to form cis-Norbornene-5,6-endo-dicarboxylic anhydride. 7-oxabicyclo2.2.1hept-5-ene-2,3-dicarboxylic anhydride was also rised by means of a Diels-Alder reaction with the combination of furan and maleic anhydride.EquationProcedure partially 1In a flask equipped with a septum post arm and topped with distillation heat and a thermometer loan 2.5ml of mineral oil. Heat the oil. At the end of the distillation heat place an ice filled beaker. When the oil reaches 250C inject 0.6ml of dicyclpentadiene drop wise through with(predicate) septum. Make sure the temperature does not go above 45C. The crossroad is accordingly weighed.Part 2In a reaction pipage place 0.20g maleic anhydride and 1.0ml of ethyl acetate then add 1.0ml of hexane. and so add 0.20ml of cyclopentadiene. Cool the tube in an ice bath. Remove solvent from crystals development p ipet. Wash crystals with hexanes then remove solvent again. Allow crystals to dry.Part 3In a flask place 2.4g maleic anhydride and add 20ml of diethyl ether. Dissolve mixture using hot plate then let cool to board temperature. Add 1.8ml of furane to the flask. Wrap the flask with Parafilm after placing a fire hydrant on top of flask. Place the flask under the hood for the adjoining lab period. Upon the return of the next class period the formed crystals were scrapped from the flask. The crystals were then weighed and melting plosives were observed.Discussion and ConclusionA Diels-Alder reaction was used to produce the products of this experiment. The first reaction was cyclopentadiene with maleic anhydride to from the product of cis-Norbornene-5,6-endo-dicarboxylic anhydride. Before that could be produced, dicyclopentadiene had to be soft to get cyclopentadiene for the starting material. Cyclopentadiene and maleic anhydride were mixed together and cooled to room temperature, w hich produced crystals. The solvent was pipette out of the tube to separate the crystals. The crystals were then scraped on the filter reputation to get weight and melting points. The end product yielded 82.6%. The melting point was observed at 162-163C. This indicated a close to pure substance with the authentic melting point being 165C. The second part of the experiment was the reaction of furan with maleic anhydride.This reaction produced 7-oxabicyclo2.2.1hept-5-ene-2,3-dicarboxylic anhydride. Maleic anhydride was combined with diethyl either to dissolve the solid. Then furan was added and place under the hood for the next class period. During this cadence crystals were formed in the stopped flask. The melting point for the end product was observed at 113-114C. This indicated that the product was exo. The percent yield was calculated at 5.98%. There were many sources of error that could start contributed to the results of these experiments.The end product could make up coole d a little longer to form more crystals. Also the crystals could have been dried more to produce better melting points. Separating the solvent from the examine tube was not completely precise and mayhave muzzy some of the product in the extraction. Scraping the crystals out of the flask or test tube was not easy and some of the product was muddled during this step. Overall the experiment was a success.ReferenceWilliamson, K. Minard, R. Masters, K. Macroscale and Microscale Organic Experiments, 2011. Pg 617-629.
Subscribe to:
Post Comments (Atom)
No comments:
Post a Comment