(Solved): Consider the reaction of 4-methyl-4-phenyl-1-butyne with \( \mathrm{HCl} \). Draw a curved arrow m ...

Consider the reaction of 4-methyl-4-phenyl-1-butyne with \( \mathrm{HCl} \). Draw a curved arrow mechanism to show the two resonance forms of the intermediate formed in the second electrophilic addition steps. You will need to modify the structure of the starting material to show this intermediate. Remember to include lone pairs and all nonzero formal charges. (1) Draw the structure of the intermediate in the second electrophilic addition and curved arrows to show resonance. \[ \rightarrow \begin{array}{l} 0 \\ 1 \end{array} \] (1) Give the structure of the second resonance form of the intermediate.