Describe the directing effect shown by the $-\mathrm{NO}_2$ group. Explain your answer.
In the nitration of arenes, a mixture of concentrated $\mathrm{HNO}_3$ and concentrated $\mathrm{H}_2\mathrm{SO}_4$ is used to produce the $\mathrm{NO_2^+}$ electrophile. Write an equation for the formation of the $\mathrm{NO_2^+}$ electrophile.
In Fig. 8.1, draw the structure of compound P in the box.
Suggest reagents and conditions for reactions 1 and 2 in Fig. 8.1. For reaction 1, give reagents and conditions. For reaction 2, give reagents and conditions.
Separate samples of $\text{C}_6\text{H}_5\text{Br}$ and $\text{C}_6\text{H}_5\text{CH}_2\text{Br}$ are each added to warm $\text{AgNO}_3\text{(aq)}$. State the observations, if any, and explain your answer. $\text{C}_6\text{H}_5\text{Br}$ with $\text{AgNO}_3\text{(aq)}$ $\text{C}_6\text{H}_5\text{CH}_2\text{Br}$ with $\text{AgNO}_3\text{(aq)}$ explanation
Acyl bromides, $\text{RCOBr}$, react readily with $\text{H}_2\text{O}$. The mechanism for this reaction is similar to the one for the reaction of $\text{H}_2\text{O}$ with acyl chlorides, $\text{RCOCl}$. Name the mechanism of this reaction.
Complete the mechanism in Fig. 8.2 for the reaction of $\text{RCOBr}$ with $\text{H}_2\text{O}$. Include all relevant lone pairs of electrons, curly arrows, charges and dipoles. Draw the structure of the intermediate.