User:PineappleCinnamon/Aromaticity

Article Draft Types of Aromatic Compounds
Aromatic molecules need not be neutral molecules. Ions that satisfy Huckel's rule of 4n + 2 π-electrons in a planar, cyclic, conjugated molecule are considered to be aromatic ions. For example, the cyclopentadienyl anion and the cycloheptatrienylium cation are both considered to be aromatic ions, and the azulene molecule can be approximated as a combination of both. '''Only one ring needs to be aromatic for an entire compound to be considered aromatic. This is the same for neutral molecules as well.'''

In order to convert the atom from sp3 to sp2, a carbocation, carbanion, or carbon radical must be formed. These leave sp2-hybridized carbons that can partake in the π system of an aromatic molecule. Like neutral aromatic compounds, these compounds are stable and form easily. The cyclopentadienyl anion is formed very easily and thus 1,3-cyclopentadiene is a very acidic hydrocarbon with a pKa of 16. Other examples of aromatic ions include the cyclopropenium cation (2 π-electrons) and cyclooctatetraenyl dianion (10 π electrons).

'''Similar to regular compounds, antiaromatic ions also exist. Antiaromatic ions, with 4n pi electrons instead of 4n + 2, are highly unstable. An example of this is cyclopentadienyl cation. This molecule follows all the rules of aromaticity except for Huckel's rule. This leads it to be an antiaromatic ion instead.'''