Finally the sidearm flask was cleaned and dried and weighed. Instead, one of the methyl groups has a higher chemical shift than the other. The two Newman projections in Figures 5 and 6 depict the stereochemical outcomes with respect to the ethane backbone within the molecule.
This was then left to stir for an additional fifteen minutes. Stereospecific products are important when a certain stereoisomer is able to be utilized while the others are not. The sidearm flask was weighed with Benzil reduction, then a 1H NMR was collected.
The melting point range of the hydrobenzoin product was found to be Stereochemical Analysis of Benzil Reduction. If we had used an acid catalyst such as hydrochloric, which is an aqueous solution, water would have been introduced to the reaction mixture.
This reaction mixture was then left to stir for another fifteen minutes. After forming the meso hydrobenzoin product, the acetal derivative was formed. The proton NMR along with the melting point range acquired, This crude oily residue was then dissolved in 10 mL of boiling petroleum ether OC and quickly hot filtered through a Hirsch funnel into a small sidearm flask to remove any insoluble unreacted diol.
Procedures taken from Dr. Since the 1H NMR of all of the stereoisomers of hydrobenzoin are nearly indentical, an acetal derivative of the product was formed Figure 4.
There are four main peaks that correspond to the product formed. The organic layer was then dried with sodium sulfate.
Results and Discussion Once the hydrobenzoin product was collected and dried, a percent yield and melting point range was obtained.
This final product was formed so as to more easily identify the stereochemistry of the hydrobenzoin product. This step is used to neutralize any acid in solution, because the acetal that is formed is stable to base hydrolysis.
This simple spectroscopy technique can allow scientists to further investigate the mechanistic principles that govern this reaction. The percent yield was found to be The collected organic extracts were then combined and washed with 10 mL of water. The acetal derivative of the hydrobenzoin product formed an oil, and a percent yield and 1H NMR of this product was able to be acquired.
In general, chemists must use similar chemical reactions in order to better understand the mechanisms involved in various processes.
The overall percent yield of this series of reactions was calculated to be This conclusion provided evidence that the meso hydrobenzoin product had been formed exclusively in the first step of the experiment. A melting point range was acquired for the hydrobenzoin product, while a 1H NMR was collected to determine if the intended final product was formed and moreover the stereochemical properties of the final product.
The reaction mechanism is shown in Figure 9.Title: Reduction: Hydrobenzoin from Benzil using Borohydride Possible Missed Points Points Name, Date, Experiment Title (abbreviated after 1st page) and every page numbered 4 OBSERVATIONS and DATA - Overall organization, readability, completeness 8 Data: Weighing data, molecular weights, moles, density, volumes, Rf’s.
Benzil Reduction Essay Words | 4 Pages. Benzil Reduction Introduction The objective of the experiment was to reduce Benzil, using sodium borohyride as the reducing agent. In a benzil reduction, there are five possible products than can occur, specifically a racemic mixture of benzoin, racemic mixture of hydrobenzoin, or meso-hydrobenzoin.
Benzil Reduction Introduction The objective of the experiment was to reduce Benzil, using sodium borohyride as the reducing agent. In a benzil reduction, there are five possible products than can occur, specifically a racemic mixture of benzoin, racemic mixture of hydrobenzoin, or meso-hydrobenzoin.
Reduce benzil using Na13H4 Collect the product using a Hirsch funnel • Weigh the product Chemical Alert benzil—irritant 95% ethanol—flammable and toxic sodium borohydride—flammal'/e and corrosive Caution: Wear departmentally approved safety goggles at all times while in the chemistry laboratory.
Caution: Benzil is an irritant.
Abstract This series of reactions (Figure 1) were carried out first using benzil and sodium borohydride to form the hydrobenzoin product, then the hydrobenzoin product was combined with anhydrous acetone and iron trichloride to form the product (4S-5R)-2,2-dimethyl-4,5-diphenyl-1,3-dioxolane.Download