CHMB42H3 Chapter Notes - Chapter 15: Aromaticity, Sodium Cyclopentadienide, Cyclic Compound
Document Summary
Aromatic compounds a cyclic and planar compound with an uninterrupted ring of p orbital-bearing atoms containing an odd number of pairs of electrons. Aliphatic compounds a nonaromatic organic compound. Benzene is a planar, cyclic compound with two cyclic clouds of delocalized electrons. Because its electrons are delocalized, all the c c bonds in benzene have the same length, shorter than a typical single bond but longer than a typical double bond. Benzene is a particularly stable compound because it has an unusually large delocalization energy. Delocalization energy (also called resonance energy) tells us how much more stable a compound with delocalized electrons is than it would be if all its electrons were localized. Compounds with unusually large resonance energies, like benzene, are called aromatic compounds. To be classified as aromatic, a compound must meet both of the following criteria: it must have an uninterrupted cyclic cloud of electrons (called a cloud) above and below the plane of the molecule.
