Aromatic Compounds Flashcards
Monosubstituted derivatives of benzene are named systematically using __________ as the parent & the substituent as a prefix
Benzene (Ex. Chlorobenzene)
What is the common name of this compound? (monosubstituted compound)
Toluene
What is the common name of this compound? (monosubstituted compound)
Phenol
What is the common name of this compound? (monosubstituted compound)
Anisole
What is the common name of this compound? (monosubstituted compound)
Aniline
What is the common name of this compound? (monosubstituted compound)
Benzoic Acid
What is the common name of this compound? (monosubstituted compound)
Benzaldehyde
What is the common name of this compound? (monosubstituted compound)
Acetophenone
What is the common name of this compound? (monosubstituted compound)
Styrene
If a substituent is larger than the benzene ring, then the benzene ring is treated as a substituent & called __________
Phenyl Group (Ex. 1-phenylheptane)
Dimethyl derivatives of benzene are called ___________
Xylene
What are the 3 constitutionally isomeric xylenes?
- ortho-Xylene
- Meta-Xylene
- Para- Xylene
What is the name of this compound? (Disubstituted methyl compound)
Ortho - Xylene (1,2-dimethylbenzene) (Ortho means 1,2)
What is the name of this compound? (Disubstituted methyl compound)
Meta - Xylene (1,3-dimethylbenzene) (Meta is 1,3)
What is the name of this compound? (Disubstituted methyl compound)
Para - Xylene (1,4-dimethylbenzene) (Para is 1,4)
Ortho, meta, & para can’t be used on aromatic ring that have _______ or more substituent
3 or more
When naming poly substituted benzene ring, we use the same method as naming alkanes but it’s common to use a ____________
Common name (Ex. 3,5,-dibromophenol)
What is the stabilization energy of benzene?
30 KJ/mol
What is the MO theory to explain the stability of Benzene?
- There are six molecular orbitals, each of which is associated with the entire molecule
- 3 of the 6 MOs are bonding MOs, while the other 3 MOs are antibonding MOs
- Since each MO can contain two electrons the 3 bonding MOs can collectively accommodate up to 6 pie electrons
- By occupying the bonding MOs, all 6 pie electron achieve a lower energy state & are said to be delocalized, which is the source of stabilization energy associated with benzene
What is Huckel’s Rule? (4n+2)
Need an odd number of electrons pairs for a compound to be aromatic (or have aromatic stabilization)
What are the steps to the frost circle?
- Draw a circle
- Inscribe a polygon making sure one of the connecting points is at the bottom of the circle
- Draw a horizontal line at each pointof intersection
- Draw a dotted line through the center of the circle & earse the circle
- Identify all the bonding MOs & antibonding MOs (bonding MOs is below the line & antibonding MOs is above the line)
What is the 2 criteria for a compound to be aromatic?
- The compound must obtain a ring comprised of continously overlapping p oribitals
- The number of pie electrons in the ring must be a huckel number
(If a compounds falls number 1 then its nonaromatic)
Compounds that satisfy the 1st criterion but have 4n electrons rather than 4n+2 are what?
Antiaromatic
Annulenes
Are compound consisting of a single containing a fully conjugated pie system