Grignard Reagent Lab Report

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Introduction:
The formation of sp2 carbons can be difficult at times because of different reaction environments can cause different outcomes of the product, which generally yields impure products or the wrong products. However, by turning the reagent into a Grignard reagent, it is possible to get a SN2 like reaction to occur most of the time which helps in the formation of certain industrial and pharmaceutical compounds. The Grignard reaction allows sp2 carbons to react with losing its hybridization, and allows carbon chains to be extended while also adding an alcohol functional group, which can be useful as seen when producing selective alcohols. This can be seen in this experiment as the formation of Malachite green, being a dye, or with …show more content…

This happens because the magnesium causes the carbon to become a nucleophile, where it attacks the carbon pushing one of the bonds to the oxygen and making it negatively charged. The anionic oxygen then attacks the hydrogen on the HCl which then protonates the oxygen giving an alcohol to form the carboxylic acid functional group as seen.
Reaction of Benzoic Acid with Grignard Reagent The reaction of benzoic acid with the Grignard reagent yields benzoic acid instead of the triphenyl molecule that was the desired outcome. This is because of steric hindrance and thermodynamic preference. Since the O-H bond is less sterically hindered than the carbon, it is broken instead of the C=O bond. The oxygen is also protonated because the bond releases more energy when bonded to hydrogen than when it bonds with a carbon, so the bonding with the hydrogen is thermodynamically preferred for the reaction. This was supported by the IR spectrum of the product of this reaction, which had similar peaks to that of the benzoic acid tested. This shows that the limitation to Grignard reagents is that they won’t work if protic hydrogens are present because the reagent will just deprotonate the alcohol, which is then protonated immediately

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Grignard Reagent Lab Report