Experiment 4 Grignard Preparation of 1,1-Diphenyl-1-propanol PDF

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synthesize 1,1-diphenyl-1-propanol from bromobenzene using a grignard reaction....

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Experiment 4: Grignard Preparation of 1,1-diphenyl-1-propanol

Abstracts: !The purpose of the research was to synthesize 1,1-diphenyl-1-propanol f using a grignard reaction. This was done by keeping conditions anhydrous. The grig synthesized by heating magnesium, then adding bromobenzene dissolved in dry ethe then heated and then cooled to room temperature. Propiophenone dissolved in dry e to the grignard. The reaction was then quenched by HCl. Layers were extracted, and then purified using trituration. IR and !1!H NMR were taken. Introduction: !The main goal of this experiment was to use a grignard reaction to m alcohol. This lab applied previous knowledge of grignard reaction mechanism to yie product. Grignard reactions are important mechanisms used to create new molecule form new carbon-carbon bonds. Results and Discussion:!Since 0.02 moles of both bromobenzene and propiophenon theoretical yield would be 0.02 moles, but only .007 moles of 1,1-diphenyl-1-propan syntheisized. Therefore, the percent yield was 35%. The IR spectra shows a strong p which points to an alcohol, and then multiple peaks around 3000 ppm pointing towa the 1!! H NMR spectra without the D20 shake, there is a strong peak at 7.3 ppm pointin groups. The is a quartet at around 2.3 ppm pointing towards a methylene group coup methyl group next to it. There is also a triplet peak at around 0.85 ppm which points group that is coupling with the methylene. An alcohol peak is not seen possibly due another singal. In the D20 shake !1!H NMR, the peaks are in the same ranges as the !1!H D2O shake, but there is a very small peak at about 4.5 that could point to and OH st noise. The D20 shake also reduced the integration number of the peak at 2.35ppm fr pointing towards the overlap of the OH signal there. In the experiment, during the washing step Et2O was added to the organic layer instead of the aqueous...