Ethanoyl nitrate

Exercise 22-10 Why is nitration with ethanoyl nitrate accelerated by added fluoro-boric acid, HBF4, but retarded by added hydrochloric acid ... 

Exercise 22-30 a. In the nitration of para-cymene by ethanoyl nitrate in ethanoic anhydride, the observed product composition at 0° is 41 % 5 and 6, 41 % 3, 8% 4, and 10% of 4-nitromethylbenzene. Use these results to determine the relative reactivities of the para-cymene ring carbons towards N02 . Give your answer relative to C3 as unity (C3 is the carbon next to the isopropyl group). Determine the relative reactivities based on the data obtained in Equation 22-1. How does neglect of ipso substitution affect calculation of relative reactivities of the ring carbons b. Write a mechanism for the solvolytic conversion of 5 and 6 to 3. 

Ethanoic anhydride reacts with concentrated nitric acid to yield the rather unstable ethanoyl nitrate (acetyl nitrate), which is a useful nitrating agent. With mixtures of benzene and methylbenzene, ethanoyl nitrate produces a mixture of nitrobenzene and 2- and 4-nitromethyl benzenes. When nitrated separately, each compound reacts at the same overall rate, but when mixed together, 25 times more nitromethylbenzene is formed than nitrobenzene. 

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