Nitration of phenols is an aromatic electrofilic substituition. It can be done under different conditions, which depend on the characteristic of the substrates. Nitrophenols are very important in industry, as they can be used in variety of different branches. Their application depends on functional groups on the benzene ring. Some of nitrophenols can be very toxic, which is why we need to be extra careful with their usage.
I performed the nitration reaction of selected phenols by using different reagents depending on the substrates. Substrates containing ethyl group, NaNO2, wet SiO2, MeOH as the solvent and with a flow of O2 was sufficient. For the substrates bearing a methoxy group, harsher reaction conditions were applied (NaNO2, concentrated H2SO4 and H2O as a solvent). Phenol derivatives with a carboxylic group were successfully nitrated using KNO3 in AcOH.
All reactions were analyzed using thin-layer chromatography (TLC) and the crude products were purified using radial chromatography. All the purified products were characterized by spectroscopic and spectrometric methods (NMR, IR, HRMS, Ttal).
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