Organic Reaction Mechanisms — Substitution, Addition and Elimination

The three great mechanism families at PGT depth: nucleophilic substitution SN1 vs SN2 (kinetics, stereochemistry, solvent effects), electrophilic addition to alkenes (Markovnikov, anti-Markovnikov, the carbocation route), elimination E1 vs E2 (Saytzeff vs Hofmann, substitution-elimination competition), and the nucleophile/electrophile vocabulary.