Benzhydrol Synthesis Lab Report

We successfully achieved our goal of synthesizing benzhydrol, but we did not successfully reach the goals of the completion of the synthesis or purification of benzhydrol.
It was clear that synthesis was of benzhydrol was taking place as the formation of the addition complex, which formed a white gunk, was present. Also, it was possible to tell the synthesis was occurring when the white gunk from the addition complex was consumed during the acid workup. During the extraction of the products there was two layers forming which also indicated that synthesis had occurred, and trace amount of white bits of product were found in the waste beaker which also indicated that synthesis occurred.
Once reaching a constant mass after driving of the excess diethyl ether, the crude product had a mass of 0.327grams and a high percent yield of 97.8%. During the first TLC examination of the crude product it was found to have 3 spots on the plate, biphenyl, benzaldehyde, and benzhydrol with Rf values of 0.68, 0.36, and 0.10 respectively. It was expected to see benzhydrol, the product, and biphenyl, the impurity, on the plate, but the presence of benzaldehyde was telling that not all of the starting material had been consumed during

the reaction, and completion was not reached during the synthesis of benzhydrol.
After the first TLC, an attempt to purify the benzhydrol of any impurities by washing it out with pet ether for 30 seconds.

After washing it out, and driving off any remaining pet ether with a water bath and reaching a constant mass, the purified product had a mass of 0.272grams. A second TLC was ran to determine if the product was now pure. The plate was found to have two spots for the pure product, benzhydrol and biphenyl with Rf values of 0.67 and 0.15 respectively. It expected to see only one spot if the product was pure, so by TLC it was able to be determined there was not purification of the benzhydrol product. The pure product had a 73.1% yield, but this does not accurately reflect the yield as there were still impurities in the pure

product.
When the IR was ran all five relevant bonds of benzhydrol, OHalc, C-Hsp3, C-Hsp2, C=Carom, and C-O, were found. The presence of the OHalc, C-Hsp3, and C-O, also show synthesis as these bonds are all absent in benzaldehyde, showing new bonds were formed.
The NMR data for benzaldehyde shows an aldehyde H as 10.0, but there is not an aldehyde H peak in the benzhydrol also showing that there was synthesis of benzhydrol.
In conclusion, in this experiment, we were successful in achieving the goal of synthesis of benzhydrol, but not successful in achieving the goals of completion of synthesis and purification of benzhydrol.