tert-Butyl Nitrite Mediated Nitro-Nitratosation of Internal Alkenes

In an oxygen atmosphere tert-butyl nitrite (TBN) reacts with unsymmetrical internal benzylic alkenes giving nitro-nitratosation product exclusively. The gamma-diaryl-substituted styrenes provided better yields compared to gamma-alkyl-aryl-substituted styrenes. The higher yields for the former type of substrates is possibly dictated by the additional stability of benzylic radical due to the anchimeric assistance imparted by the gamma-substituted phenyl ring. During oxidative nitration, the nitro (NO2) group adds at the non-benzylic site, whereas the nitrato group (ONO2) is attached at the relatively stable benzylic position. Under similar reaction conditions, alpha,beta-unsaturated carboxylic acids, afforded nitroalkenes as the sole product.