Arenes
Reactions
Electrophilic Substitution
\(\require{mhchem}\ce{Benzene + Cl_2 -> Chlorobenzene + Cl^-}\)
\(NO_2\ ^+\) can be replaced with any other electrophile (e.g. \(^+CH_3\))
Side-chain substitution
Same as alkane
Substituents
| \(e^-\) withdrawing | \(e^+\) donating | \(-X\) groups | |
|---|---|---|---|
| AKA | Deactivating Groups | Activating Groups | Activating |
| Example Groups | \(-COOH\), \(-COOR\), \(-C≡N\), \(-CONR\) | \(-R\), \(-OR\), \(-OH\), \(-NR_2\) | \(-Cl\), \(-Br\) |
| Features | Unsaturated | Saturated | Saturated |
| Rate of rxn | Decreased | Increased | Increased |
| Why? | Decreased electron density, less susceptible to electrophilic attacks | Increased electron density, more susceptible to electrophilic attacks | Backdonation |
| Directing Positions | 1, 3, 5 | 2, 4, 6 | 1, 3, 5 |