Heteropolyacids as an efficient and reusable catalytic system for the regiospecific nitration of phenols with metal nitrates

Highly regiospecific mononitration of phenols and substituted phenols is accomplished employing a metal nitrate and a catalytic amount of heteropolyacid in acetonitrile. An exclusive ortho-selectivity was observed with excellent yields. A variety of metal nitrates were used to obtain o-nitrophenols exclusively in good to excellent yields. The use of heteropolyacid is key for the selectivity observed.DOI: http://dx.doi.org/10.4314/bcse.v26i1.17