Diels alder reaction Essay

ResultFor the Diels-Alder reactionMaleic acid is 0.002 groin2,3-dimethyl-1,3-butadiene is 0.002 molThe theoretical have a bun in the oven is 0.36gCycloaddition product is 0.358g (maybe it was not completely dry when I weighted.) The % yield of Diels-Alder reaction is 99.4%For the hydrolysisThe theoretical yield of hydrolysis is 0.396gThe experimental product yield is 0.28g (some solid left on the filter paper and some for the melt heighten measurement.)The % yield of hydrolysis is 70.7%The cycloaddition of a conjugated diene and a dienophile, which is drove by forming new -bonds from -electrons of the diene and dienophile, which are energetically more stable than the -bonds.During the Diels-Alder reaction, the temperature should be unbroken between 60-70 . Because the boiling point of the butadiene is low and do not let it vaporize. After cycloaddition, pour the reaction mixture into 50 ml pissing under room temperature, the product would precipitate because of the low temperat ure. The acid added for the hydrolysis exposit is very important because acids have been used to accelerate the rate of the intra-molecular Diels-Alder reaction.The nab 200 used in this experiment as the solvent for maleic anhydride is nonplus the experiments more green, which is less harmful and more environmental friendly. The melting point measurement is helping us to determine what we get basically.Compare with the IR spectra I got, the peak at 1792.62 cm-1 in the first spectra express the C=O bonds of the initial cycloaddition product, and the peak at 1697.14 cm-1 in the second IR spectra shows the C=O bonds of carboxylic acid ( RCOOH) of the final product.