Safer Preparation of m-CPBA/DMF Solution in Pilot Plant

The usage of m-CPBA (meta-chloroperbenzoic acid) is limited on large scale due to its thermal instability, although it is a good oxidant and well-accepted in laboratory scale. In our recent project, m-CPBA was used for an oxidation reaction, and an explosion hazard was identified. To ensure the safe use of m-CPBA on large scale, the stability of m-CPBA in different solvents was investigated, and it was found that besides the incompatibility between m-CPBA and DMF reported earlier, the intrinsic instability of m-CPBA/DCM solution at high concentration (low onset temperature and large exotherm) can also cause a major problem on large scale. Therefore, process parameters such as concentration of m-CPBA, addition sequence, and handling temperature have been investigated and successfully applied in pilot plant for a large scale reaction using 8 kg of m-CPBA.