When chemists are developing processes in the laboratory on small scale the reactions will often be selective for the desired product, partly as a result of the reaction conditions chosen by the chemist and partly because the reactions are usually well mixed. During development, it is important that work is carried out that is relevant to the likely operational conditions at scale so issues such as rate of reagent addition, point of addition and impact of agitation are evaluated to guide the development of the process and not just the chemistry