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Phenylmethanol (benzyl alcohol) is converted into (chloromethyl)benzene in the presence of hydrogen chloride much more rapidly than ethanol is converted into chloroethane. Explain.

Why is 3 -nitrophenol (m-nitrophenol) less acidic than its 2 - and 4 -isomers but more acidic than phenol itself?

1-Chloro-4-methylbenzene ( \(p\) -chlorotoluene) is not a good starting material for the preparation of 4-methylphenol ( \(p\) -cresol) by direct reaction with hot \(\mathrm{NaOH}\), because it forms a mixture of two products. Why does it do so, and what are the two products?

Propose a synthesis of \(1,3,5\) -tribromobenzene from benzene.

Write the products of diazo coupling of benzenediazonium chloride with each of the following molecules. (a) Methoxybenzene; (b) 1 -chloro-3-methoxybenzene; (c) 1 -(dimethylamino)-4(1,1-dimethylethyl)benzene. (Hint: Diazo couplings are quite sensitive to steric effects.)

Predict the order of relative stability of the three benzylic cations derived from chloromethylbenzene (benzyl chloride), 1 -(chloromethyl)-4-methoxybenzene (4-methoxybenzyl chloride), and I-(chloromethyl)-4-nitrobenzene (4-nitrobenzyl chloride). Rationalize your answer with the help of resonance structures.

In nucleophilic aromatic substitution reactions that proceed by the addition- elimination mechanism, fluorine is the most casily replaced halogen in spite of the fact that \(\mathrm{F}^{-}\) is by far the worst leaving group among halide ions. For example, 1 -fluoro- 2,4 -dinitrobenzene reacts much more rapidly with amines than does the corresponding chloro compound. Suggest an explanation. (Hint: Consider the effect of the identity of the halogen on the rate-determining step.)

What is the principal product after the slurry obtained on treating benzenamine (aniline) with potassium nitrite and HCl at \(0^{\circ} \mathrm{C}\) has been added to 4 -ethylphenol?