Naphthalene

anthracene

Philippines

2 substituents

3 substituents

The electron cloud of benzene is like two breads sandwiching the nucleus - a hamburger, so the reagent attacks the benzene ring and reacts with the electron cloud first - electrophilic reaction

Halogenation reaction (using FeX3 as catalyst)

nitrification reaction

Sulfonation reaction

Friedel-Crafts reaction

H2

Cl2

Side chain oxidation

Benzene epoxidation

Except for halogen, all activate ph - the halogen-induced effect-I is too strong and passivates ph (so it has the smallest impact among this type of positioning base)

All passivation

The atom directly connected to ph has only a single bond - the first type of substituent

The atom directly connected to ph contains double or triple bonds or has a positive charge - the second type of substituent

Observe the groups connected to ph and mark d and d- (alternating). The d/d- of the atomic band directly connected to ph will affect the electron cloud arrangement of ph.

Homogeneous groups

Different types of groups

Pay attention to steric effects

Numbering starts from position a. The two shared Cs will not have substituents, so they are not numbered.

Numbering starts from the a position closest to the main functional group

minimal principle

Finish one loop first, then another one

Substitution reaction: generally occurs at the a position - special case: sulfonation of naphthalene -80°C to obtain a-naphthalene sulfonic acid; 165°C to obtain b-naphthalene sulfonic acid

addition reaction

Note that it is provided by the ring-forming atoms, and the p electrons provided by conjugation with it are not included if they are not atoms in the ring, e.g. chlorobenzene