Ethanol (4.0 mL) and benzoin (0.5004 g) were added to an 25 mL Erlenmeyer flask. The flask was first swirled at room temperature for the solutes to dissolve. Some heat was also added to facilitate the dissolving. Once completely dissolved, sodium borohydride (NaBH4) (0.102 g) was added with a microspatula over the course of several minutes. After, the mixture was swirled for 20 minutes at room temperature. 5 mL of water and 0.3 mL of 6M hydrochloric acid were added to the flask after being cooled in an ice bath. 2.5 mL of water was then added to quench the solution. 1,2-diphenylethane-1,2 diol was collected with the vacuum filtration and rinsed with ice cold water. The product was left to dry for 15 minutes on the filter. Once the product was weighed, the crude yield mass was determined of 0.512 g. The crude product was then recrystallized with 1.5 mL of acetone. Once the crystals were dry, the melting point of the purified 1,2-diphenylethane-1,2 diol was measured to be 137 degrees celsius and the percent yield and mass yield were.
Recent comments