2-Methylcyclohexanone Lab Report

In this experiment, racemic 2-methylcyclohexanone was reduced using sodium borohydride as a nucleophile to give a diastereomeric mixture of cis and trans secondary alcohols. The products were analyzed for purity using IR spectroscopy and gas chromatography. 1.2 g of 2-methylcyclohexanone and 10 mL of methanol were combined in a flask and cooled in an ice bath. Two 100 mg portions of sodium borohydride were added to the flask and stirred. 5 mL of 3M sodium hydroxide, 5 mL of de-ionized water, and 15 mL of hexane were added to the reaction flask and stirred. The mixture was transferred to a separatory funnel, separated into an organic layer and water layer, and then drained. The water layer was washed twice with 10 mL of hexane. The organic layer was dried

An infrared spectrum was run on the product to be compared to the starting material. The starting material had peaks at 2900 cm-1, and 1700 cm-1, corresponding to the Csp3-H of alkanes, and the C=O of a carbonyl ketone. The product’s IR spectrum had a peak at 3400 cm-1 and 2900 cm-1, indicating the prescence of an alcohol and Csp3-H of alkanes. The Jones test was performed using cyclohexanol and cyclohexanone as controls, and testing the starting material, 2-methylcyclohexanone, and the product. The product yielded a positive result, indicating the presence of an alcohol functional group. Brady’s test was also run and the product yielded a negative result, indicating there was no ketone present. These tests together indicate that the starting material fully reacted to form the product because the starting material had a ketone and the product did not have the ketone but rather had an alcohol. The gas chromatogram of the product was analyzed and had two peaks, the first at retention time 26.2 min and A of 125.33, with a concentration of 120.69, the second at retention time 27.2 min and A of 496.33, with a concentration of