Electron Donating and Electron withdrawing groups

Aromaticity and Benzene rxtns

Ortho position

1,2 position

Meta position

1,3 position

Para Position

1,4 position

Strongly deactivating groups are. (EWG)

CN, NR3, and NO2

they are META directors

moderate deactivating groups (EWG)

Ketone / acyl group

Ester

Carboxylic acid

Sulfonic acid

META directors

weakly deactivating groups (EWG)

F, Cl, Br, I

these are the exception

ORTHO/PARA directors

Weakly activating groups (EDG)

alkyl group

ORTHO PARA directors

moderate/strong activating groups (EDG)

Thioether (sulfide)

Thiol

Ether / alkoxy group

Alcohol / hydroxyl group

Ester

Amide

ORTHO PARA directors

most strongly activating (EDG)

Primary amine

Secondary amine

Tertiary amine

ORTHO PARA directors

When multiple substituents are on ring which is the director?

The more activating/EDG of the two

Acyl groups are

meta directors

What needs to be present for a benzylic oxidation to occur

must have at least one benzylic hydrogen

Aromaticity rules

1. The compound must be cyclic.

2. The ring must be fully conjugated and planar (none of the atoms comprising the ring are sp3

.......hybridized).

3. The system must satisfy Huckel’s rule (# of pi electrons = 4n+2; n is any integer).

Anti aromatic breaks which rule

huckles rule but follow all others