14.1: Overlap of Three Adjacent p Orbitals: Electron Delocalization in the 2-Propenyl (Allyl) System 14.2: Radical Allylic Halogenation 14.3: Nucleophilic Substitution of Allylic Halides: SN1 and SN2 14.4: Allylic Organometallic Reagents: Useful Three-Carbon Nucleophiles 14.5: Two Neighboring Double Bonds: Conjugated Dienes 14.6: Electrophilic Attack on Conjugated Dienes: Kinetic and Thermodynamic Control 14.7: Delocalization among More than Two Pi Bonds: Extended Conjugation and Benzene 14.8: A Special Transformation of Conjugated Dienes: Diels-Alder Cycloaddition 14.9: Electrocyclic Reactions 14.10: Polymerization of Conjugated Dienes: Rubber 14.11: Electronic Spectra: Ultraviolet and Visible Spectroscopy