In the correct boxes, sketch the skeletal formulae of the four structural isomers. The number of peaks seen in the carbon-13 ($^{13}\text{C}$) NMR spectrum for each compound is stated.
Step 1 is electrophilic substitution alkylation of benzene. Use $\text{R--Cl}$ to stand for $\text{Cl}(\text{CH}_2)_3\text{CO}_2\text{H}$. Write an equation showing the creation of an electrophile from $\text{R--Cl}$ and $\text{AlCl}_3$.
Infer and draw the structures of $\text{W}$ and $\text{X}$ in the boxes.
Suggest the reagents and conditions for step 2.
Finish the mechanism for the reaction of benzene with the electrophile formed in (b)(i). Show all relevant charges and curly arrows to indicate the movement of electron pairs. Draw the structure of the intermediate.