Class Notes (836,414)
Canada (509,777)
Chemistry (378)

Chem 2213 Topic 6 Notes.docx

1 Page
Unlock Document

Chemistry 1027A/B
Mel Usselman

Key Concepts In Organic Chemistry: Arenes (Usselman Version) -Benzene has 4 units of unsaturation, but is remarkably stable. All compounds containing the benzene ring system do not undergo any of the typical alkene reactions do to its supreme stability. Benzene compounds have come to be known as aromatic compounds, though many of them are toxic and carcinogenic. The benzene group of compounds are known as arenes and substituents containing an aromatic group are named as aryl substituents (given the symbol Ar). The lobes of the 6 p orbitals gives a molecular orbital with electron density above and below the ring plane (torus configuration). Benzene is more stable than a cyclohexane ring containing 3 C = C. This increased stability due to resonance is called its resonance energy. -Resonance stabilization is the central feature, termed aromaticity, of all ring compounds (aromatic compounds). The requirements for aromaticity are: i) rings that are planar, ii) one 2p orbital on each ring atom, and iii) 4n + 2 (2, 6, 10, etc) π electrons in all ring orbitals. Rings that contain heteroatoms (atoms other than C and H) are also aromatic. It is important to recognize that the heteroatoms N and O 2 in pyrrole and furan respectively become sp hybridized. -When a benzene ring is named as substituent in a molecule it is called phenyl (Ph). Another aromatic substituent is called benzyl (Bz), which is a benzene ring attached to a CH grou2. For substituents on a benzene ring a special naming convention is used: 1,2 substituents = ortho (o). 1, 3 substituents = meta (m). 1,4 substituents = para (p). The substituent responsible for the compound’s common name is always assigned position #1. Aromatic compounds are
More Less

Related notes for Chemistry 1027A/B

Log In


Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.