If the 6-C benzene is parent chain, use _________ as parent

Benzene

If the hydrocarbon is parent chain, use _______ as substituent

Phenyl

A phenylmethyl substituent is referred to as _____

Benzyl

For disubbed benzenes, what's important to include in naming?

Ortho, Meta, Para

T/F: Benzene rings exhibit decreased stability

False, they are very stable

What is aromaticity?

Stabilizing effect that results from delocalization of pi e- in planar, cyclic conjugated molecule

What is an annulene? Is benzene and annulene?

- Cyclic hydrocarbon w/ alternating single and double bonds - Yes

A compound is aromatic if.... 3

- Cyclic - Continuous overlapping p orbital in planar - # of pi e- in ring is 4N + 2 (N is integer)

A compound is antiaromatic if.... 3

- Cyclic - Continuous overlapping p orbital in planar - # of pi e- in ring is 4N (N is integer)

A compound is nonaromatic if... 2

Acyclic or DOES NOT Continuous overlapping p orbital in planar

T/F: Cyclooctatetraene is nonaromatic

True - It is too large and not planar

The energies of pi-MO's for cyclic systems can be predicted by ________

Frost circles

Which is more stable: benzene or 1,3,5-hexatriene (acyclic)? Why?

- Benzene - Benzene is more stable because it is aromatic

Which is more stable: cyclobutadiene or 1,3-butadiene? Why?

1,3-butadiene - In cyclobutadiene, 2 of the 4 pi e- are unpaired an exist in non-bonding MO's

What is diradical character?

Some pi e- exist unpaired and in nonbonding MO's

T/F: aromatic cation/anion is more stable than antiaromatic or nonaromatic analogue

True

If an anion is aromatic and the cation is antiaromatic, what is easier to generate?

The anion

What are heterocytes?

Cyclic molecules that contain molecules other than carbon

The LP's of ____________ can contribute to resonance and aromaticity 3

N, S, or O

How can LP's contribute to resonance?

Needs to be in p orbital Needs to be conjugated Ex. If a p+ is attached then it does contribute