Grignard Reaction Discussion

In this experiment we used a Grignard reaction to form triphenylmethanol. The synthesis of our Grignard reagent was required for this experiment, therefore, phenylmagnesium bromide was produced from bromobenzene and magnesium before the preparation of triphenylmethanol. At the completion of the lab we were able to successfully conclude that our reaction went to completion form triphenylmethanol. Through calculations of percent yield, we concluded that there was a 15.63% of bromobenzene was successfully reacted into Triphenylmethanol and a 77.78 % recovery from our crude product to our purified product.

A melting point analysis was conducted to test the purity of our product, with a literature value for triphenylmethanol being 160- 163 ℃, our triphenylmethanol had a melting point of 160 ℃. Our mixed product analysis (included the standard and our product) had a melting point of 163 ℃. These tests allowed us to confirm the purity and identity of our product as triphenylmethanol. From our IR spectra, we are able to identify a broad -OH bond at 3472.5 cm -1, aromatic -C-H peaks closer to 3061.0 cm -1, aromatic ring stretches around 1958.2 - 1445.5 cm-1 and the clear indication of a missing ketone stretch which should have been located at 1715 cm­-1. This analysis further proves our product was successful from benzophenone to triphenylmethanol.

Though the results from our analysis illustrate the success of our production of triphenylmethanol from a Grignard reaction, the percent yield of product was very low which could have been due to a number of human errors within our experiment.