ochem 2 lab gringard reagent

This solution was allowed to stir and remain at

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This solution was allowed to stir and remain at reflux for ten minutes. Then 9.05 g of benzophenone was measured out and dissolved within 100 mL anhydrous ethyl ether which was placed within a separatory funnel. This was added dropwise to the Grignard reagent, at which point the solution was placed on a steam bath and allowed to reflux for fifteen minutes. After which the solution was cooled to room temperature and then was placed on ice to cool further. A cold acidic solution was then prepared by measuring out 4.5 mL of H 2 SO 4 and placing it within a beaker that was filled with ice. This then gave about 30 mL of solution. 35 mL of water was added to a 250 mL beaker, which then had the 30 mL of acid poured into it. Ice was used to keep this solution cool, until it was combined with the Grignard solution. Once the entire solid reacted the reaction mixture was poured into a 500 mL separatory. The organic layer was saved and the aqueous layer was transferred back into the separatory funnel so that it could be extracted twice more using 50 mL of ethyl ether each time. The organic layer was dried using MgSO 4 and decanted into an Erlenmeyer flask. It was then placed over a steam bath until a precipitate formed which was then collected. 150 mL of methanol was heated to a boil, and added to the collected precipitate. Only enough methanol was added so that the entire solid dissolved. During this process the solution was swirled over a steam bath. Once all of the solid was dissolved it was placed upon the steam bath before being cooled to room temperature. When the solution reached room temperature it was placed on ice, and vacuum filtration was performed on the subsequent crystals. A watchglass was weighed at 54.8 g and the crystals were then placed on it.
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The watch glass was then weighed at 61.11 g when the crystals were dry. An IR and a melting point were performed on the dried crystal solids. Results: The mass of the dried sample plus the watch glass weighed 61.11 g and the mass of the watch glass by itself was 54.8 g. The total mass of the dried crystals after recrystallization was 6.31 g, which is 0.02424 mol. The mass of the starting benzophenone was 9.1 g or 0.04967 mol. The percent yield for the product was calculated to be 51.2% using the following equation: % Yield = x 100 The literature percent yield for the product triphenylmethanol is 89-93%. The collected melting point range of the pure triphenylmethanol was 160-162.5°C. The melting point for triphenylmethanol within the literature is 160-163°C. The key IR peaks obtained from the performed IR spectra on the resulting pure product are as follows: Absorption(cm -1 ) Bond Type 3472.68 Oxygen-Hydrogen: Alcohol 1596.70 Carbon-Carbon: Aromatic 3058.97 C (aromatic) - H 1010.45 Sp 3 Carbon-Oxygen Table 2: Fundamental IR Peaks and their Corresponding Bonds The IR frequencies that should be expected for triphenylmethanol and that would be cited within the literature are a broad alcohol peak from 3200-3500 cm -1 , a carbon-carbon aromatic peak from 1500-1600 cm -1 , an aromatic carbon hydrogen peak at approximately 3030 cm -1 , and a sp 3
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