"Benzene is resonance stabilized, as shown above, and is sometimes drawn in the following way This type of drawing a hexagon with a circle in the center is not suitable when drawing mechanisms of reactions, because mechanisms require that we keep track of electrons meticulously. But, it is helpful to see this type of drawing, even though we won't use it again in this book, because it represents all six electrons of the ring as a single entity, rather than as three separate bonds. Indeed, a benzene ring should be viewed as one functional group, rather than as three separate functional groups.…mehr
"Benzene is resonance stabilized, as shown above, and is sometimes drawn in the following way This type of drawing a hexagon with a circle in the center is not suitable when drawing mechanisms of reactions, because mechanisms require that we keep track of electrons meticulously. But, it is helpful to see this type of drawing, even though we won't use it again in this book, because it represents all six electrons of the ring as a single entity, rather than as three separate bonds. Indeed, a benzene ring should be viewed as one functional group, rather than as three separate functional groups. This is perhaps most evident when we consider the special stability associated with a benzene ring. To illustrate this stability, we can compare the reactivity of cyclohexene and benzene"--Hinweis: Dieser Artikel kann nur an eine deutsche Lieferadresse ausgeliefert werden.
David Klein is a lecturer at Johns Hopkins University where he teaches Organic and General Chemistry. He is a dynamic and creative teacher and uses analogy to help students grasp difficult topics. Klein's unique informal voice and manner of presentation help students truly master key topics in this course. He is also the author of Organic Chemistry as a Second Language; response to this book has been phenomenal.
Inhaltsangabe
CHAPTER 1 AROMATICITY 1 1.1 Introduction to Aromatic Compounds 1 1.2 Nomenclature of Aromatic Compounds 2 1.3 Criteria for Aromaticity 6 1.4 Lone Pairs 9 End-of-Chapter Problems 11 CHAPTER 2 IR SPECTROSCOPY 14 2.1 Vibrational Excitation 14 2.2 IR Spectra 16 2.3 Wavenumber 16 2.4 Signal Intensity 21 2.5 Signal Shape 22 2.6 Analyzing an IR Spectrum 29 End-of-Chapter Problems 36 CHAPTER 3 NMR SPECTROSCOPY 39 3.1 Chemical Equivalence 39 3.2 Chemical Shift (Benchmark Values) 42 3.3 Integration 47 3.4 Multiplicity 50 3.5 Pattern Recognition 52 3.6 Complex Splitting 54 3.7 No Splitting 55 3.8 Hydrogen Deficiency Index (Degrees of Unsaturation) 56 3.9 Analyzing a Proton NMR Spectrum 59 3.10 13C NMR Spectroscopy 63 End-of-Chapter Problems 65 CHAPTER 4 ELECTROPHILIC AROMATIC SUBSTITUTION 78 4.1 Halogenation and the Role of Lewis Acids 79 4.2 Nitration 83 4.3 Friedel-Crafts Alkylation and Acylation 85 4.4 Sulfonation 92 4.5 Activation and Deactivation 96 4.6 Directing Effects 98 4.7 Identifying Activators and Deactivators 107 4.8 Predicting and Exploiting Steric Effects 117 4.9 Synthesis Strategies 124 End-of-Chapter Problems 129 CHAPTER 5 NUCLEOPHILIC AROMATIC SUBSTITUTION 134 5.1 Criteria for Nucleophilic Aromatic Substitution 134 5.2 SNAr Mechanism 136 5.3 Elimination-Addition 142 5.4 Mechanism Strategies 148 End-of-Chapter Problems 151 CHAPTER 6 KETONES AND ALDEHYDES 154 6.1 Preparation of Ketones and Aldehydes 154 6.2 Stability and Reactivity of C=O Bonds 157 6.3 H-Nucleophiles 159 6.4 O-Nucleophiles 164 6.5 S-Nucleophiles 174 6.6 N-Nucleophiles 176 6.7 C-Nucleophiles 184 6.8 Exceptions to the Rule 193 6.9 How to Approach Synthesis Problems 197 End-of-Chapter Problems 203 CHAPTER 7 CARBOXYLIC ACID DERIVATIVES 207 7.1 Reactivity of Carboxylic Acid Derivatives 207 7.2 General Rules 208 7.3 Acid Halides 212 7.4 Acid Anhydrides 220 7.5 Esters 222 7.6 Amides and Nitriles 231 7.7 Synthesis Problems 240 End-of-Chapter Problems 247 CHAPTER 8 ENOLS AND ENOLATES 253 8.1 Alpha Protons 253 8.2 Keto-Enol Tautomerism 255 8.3 Reactions Involving Enols 259 8.4 Making Enolates 262 8.5 Haloform Reaction 265 8.6 Alkylation of Enolates 268 8.7 Aldol Reactions 272 8.8 Claisen Condensation 278 8.9 Decarboxylation 285 8.10 Michael Reactions 292 End-of-Chapter Problems 299 CHAPTER 9 AMINES 303 9.1 Nucleophilicity and Basicity of Amines 303 9.2 Preparation of Amines Through SN2 Reactions 305 9.3 Preparation of Amines Through Reductive Amination 308 9.4 Acylation of Amines 313 9.5 Reactions of Amines with Nitrous Acid 316 9.6 Aromatic Diazonium Salts 319 End-of-Chapter Problems 322 CHAPTER 10 DIELS-ALDER REACTIONS 325 10.1 Introduction and Mechanism 325 10.2 The Dienophile 328 10.3 The Diene 329 10.4 Other Pericyclic Reactions 335 End-of-Chapter Problems 336 Detailed Solutions S-1 Index I-1
