Question

5. What is the function of the charcoal in the purification of the 4-nitroaniline? (3 marks) 6. Why it is not possible to obtain 2- and 4-nitroaniline by direct nitration of aniline? (3 marks) 7. Explain with the use of appropriate resonance structures, the regioselectivity of the electrophilic aromatic substitution reaction - i.e. why is electrophilic aromatic substitution of acetanilide less favoured at the 3-position than at the 2- or the 4-positions. (6 marks) 8. Predict how a 'H NMR spectrum of 4-nitroaniline in CDCls would appear. (9 marks) Predict means propose approximate chemical shift, multiplicity coupling data and relative integral for signals representing all protons in the compound. In your answer use a table as indicated in Section 2.3 REPORTING EXPERIMENTAL WORK