[BausUCB]

In my lab I used Suzuki coupling to react 4-bromoacetophenone to phenylboronic acid to get 4-acetlybiphenyl. For some reason in my 1H NMR I'm getting a rather large peak at around 4.8 ppm that I think may be from some byproduct or side reaction. The reaction was done under palladium catalysis with potassium carbonate as the base and tetra butyl ammonium chloride as a phase transfer agent. These were removed by washing with water and centrifuging.

[phth]

Some peak at 4.8 ppm is not very descriptive.  Depends on the solvent.  I am guessing it's not CDCl₃ and you may have used DCM?  What is the splitting, singlet? Is it a broad peak i.e. HDO? What does the concentrated TLC look like?  There could be several reasons why.  What is your yield?  You could deduce what it is if you know the % weight, and things of this nature.