ORGANIC CHEMISTRY Chapter 15 15.14A USe of Protecting and Blocking Groups o Strong activating groups such as amino and hydroxyl cause the aromatic ring to be so reactive that unwanted reactions can take place o These groups activate aromatic rings to oxidation by nitric acid when nitration is attempted; the ring is destroyed OH OH HNO nO, HoSO t Oxidation products NO2 Low yield Department of Chemistry, Xiamen UniversityORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 15 15.14A Use of Protecting and Blocking Groups Strong activating groups such as amino and hydroxyl cause the aromatic ring to be so reactive that unwanted reactions can take place. These groups activate aromatic rings to oxidation by nitric acid when nitration is attempted; the ring is destroyed. OH HNO3 H2SO4 OH OH NO2 NO2 + + Oxidation products Low yield