Contents Introduction to Heterocyclic Chemistry 1 1.1 Coverage 12 nclature Importance to Life and Industry 1.4 General Principles 46 Pyridine 18 2.1 Resonance Description 2.2 Electrophilic Substitution 189 Pyridine N-Oxides 22 Nucleophilic Substitution 2.5 Lithiation e 2.6 Methods of Synthesis 28 2.7 Commonly Encountered Pyridine Derivatives 2.8 Reduc ed Pyridine 36 3 Benzopyridines 42 3.1 Introduction 42 3.2 Quinoline 3.3 Isoquinoline 50 4 Pyrylium Salts,Pyrans and Pyrones 58 4.1 Introduction 4.2 Pyrylium Salts 58Contents I Introduction to Heterocyclic Chemistry 1.1 Coverage 1.2 Nomenclature 1.3 Importance to Life and Industry 1.4 General Principles 2 Pyridine 2.1 2.2 2.3 2.4 2.5 2.6 2.7 2.8 Resonance Description Electrophilic Substitution Pyridine N-Oxides Nucleophilic Substitution Lit hiat ion Methods of Synthesis Commonly Encountered Pyridine Derivatives Reduced Pyridines 3 Benropyridines 3.1 Introduction 3.2 Quinoline 3.3 Isoquinoline 4 Pyrylium Salts, Pyrans and Pyrones 4.1 Introduction 4.2 Pyrylium Salts i 18 18 19 22 23 28 28 29 36 42 42 43 50 58 58 59 V