6 TUTORIAL CHEMISTRY TEXTS RS·C ROL SOCETY OF CHEMSTRY Functional Group Chemistry by JAMES.R.HANSON
Preface The aim of this book is to provide an introduction to the characteristic properties of functional groups.It is written for first-year undergraduates. The book is in four chapters.The first is devoted to a general considera- tion of the bonding in functional groups.the classes of reagent and the types of r first of the se are p ay be divided into eral broad functional groups which the tions,mainly substitution and elimination,are those chemistry of these functional groups forms the second chapter.A second class of functional groups is those in which a n-bond is a characteristic feature.The initial step in many of their reactions is an addition.These functional groups are described in the third chapter.The electrons within a -bond may be symmetrically distributed as in an alkene,or unsymmetri- cally distribute as in the carbo alCOntcmgp n The ys a o. part in funct group che mistry. The chapter is voted to escription of the interaction between functional groups and ring.Heteroaromatic compounds are considered in terms of the perturba- tion of the n-system brought about by the insertion of the heteroatom. A balance has to be drawn in the use of systematic and trivial names. The IUPAC rules recognize that the use of trivial names for many simple ofter referred.Students will meet these names in the currer nt lite on ttles in the labo Howe because the systematic nomencla ture basis docum nting more complex structures,students need to be familiar with the use of sys tematic nomenclature by applying it to simple molecules.Both names will be given for compounds at appropriate stages in the text.An Appendix of Common and Systematic Names can be found on the RSC website (http://www.chemsoc.org/pdf/tct/functionalappendix.pdf),as well as a Further Reading list(http://www.chemsoc.org/pdf/tct/functionalreading am indebted to Martyn Berry and Professor Sir John Cornforth AC FRS for their many valuable comments on the draft manuscript and par. ticularly to Professor Alwyn Davies FRS for his substantial help and encouragement throughout the preparation of the manuscript and dia- grams. J.R.Hanson Sussex
Preface The aim of this book is to provide an introduction to the characteristic properties of functional groups. It is written for first-year undergraduates. The book is in four chapters. The first is devoted to a general consideration of the bonding in functional groups, the classes of reagent and the types of reaction. Functional groups may be divided into several broad classes. The first of these are those functional groups in which the reactions, mainly substitution and elimination, are those of the o-bond. The chemistry of these functional groups forms the second chapter. A second class of functional groups is those in which a x-bond is a characteristic feature. The initial step in many of their reactions is an addition. These functional groups are described in the third chapter. The electrons within a n-bond may be symmetrically distributed as in an alkene, or unsymmetrically distributed as in the carbonyl group. The aromatic ring plays a major part in functional group chemistry. The final chapter is devoted to a description of the interaction between functional groups and the aromatic ring. Heteroaromatic compounds are considered in terms of the perturbation of the x-system brought about by the insertion of the heteroatom. A balance has to be drawn in the use of systematic and trivial names. The IUPAC rules recognize that the use of trivial names for many simple compounds is often preferred. Students will meet these names in reading the current literature and on the bottles in the laboratory. However, because the systematic nomenclature forms the basis of documenting more complex structures, students need to be familiar with the use of systematic nomenclature by applying it to simple molecules. Both names will be given for compounds at appropriate stages in the text. An Appendix of Common and Systematic Names can be found on the RSC website (h t tp://www.chemsoc, org/pdf/tct/functionalappendix. pdf), as well as a Further Reading list (http://www.chemsoc.org/pdf/tct/functionalreading. I am indebted to Martyn Berry and Professor Sir John Cornforth AC FRS for their many valuable comments on the draft manuscript and particularly to Professor Alwyn Davies FRS for his substantial help and encouragement throughout the preparation of the manuscript and diagrams. J. R. Hanson Sussex PdQ
Contents 1 General Principles 1.1 The Strueture of Functional Groups Reagents and Rea tion Learning Organic Functional Group Chemistry 1218 2 Chemistry of the c-Bond 24 24 Alkyl Halides 2.3 Alcohols 33 2.4 Epoxides and Ethers 43 Organosulfur Compounds 2.6 Aliphatic Amines 51 3 Chemistry of the n-Bond Alkenes Alkynes 3.3 Carbonyl Compounds 469 3.4 Carboxylic Acids and their Relatives 3.5 Enolate and Related Carbanion Chemistry 100 3.6 Nitriles,Imines and Nitro Compounds 4 Chemistry of Aromatic Compounds 115 4.1 Aromatic Substitution 115
Contents 1.1 The Structure of Functional Groups 1.2 Reagents and Reactions 1.3 Learning Organic Functional Group Chemistry 2.1 Alkanes 2.2 Alkyl Halides 2.3 Alcohols 2.4 Epoxides and Ethers 2.5 Organosulfur Compounds 2.6 Aliphatic Amines 3.1 Alkenes 3.2 Alkynes 3.3 Carbonyl Compounds 3.4 Carboxylic Acids and their Relatives 3.5 Enolate and Related Carbanion Chemistry 3.6 Nitriles, Imines and Nitro Compounds 4.1 Aromatic Substitution 1 12 18 24 27 33 43 48 51 64 76 79 92 100 105 115 V
vi Contents 4.2 Aromatic Functional Groups 123 4.3 Heteroaromatic Compounds 133 Answers to Problems 147 Subject Index 164
vi Contents 4.2 Aromatic Functional Groups 4.3 Heteroaromatic Compounds 123 133
1 General Principles Aims The aims of the first chapter of this book are to provide the foun. The relationship between bonding and structure of organic compounds 。 The oxidative and substitutive relationship between functional groups The relationship between electronegativity differences and the reactivity of functional groups The kinetic and thermodynamic control of reaction products 1.1 The Structure of Functional Groups A functional group isa chemically reactive group of atoms within molecule.Each may be modified by its position within the molecule or by the presence of other neighbouring functional groups. 1.1.1 Hybridization and Bonding aiolaicdet2o0roiCaPGaoekceoetronsini1sooa of pomding found arbon compounds eomrou ybid of the 2s and 2p orbitals.Combination of one 2s and three 2p orbitals
General Principles 1.1 The Structure of Functional Groups A is a chemically reactive group of atoms within a molecule. Each functional group has its characteristic reactivity, which may be modified by its position within the molecule or by the presence of other neighbouring functional groups. I =l =I Hybridization and Bonding An isolated carbon atom possesses two electrons in its 1s orbital, two electrons in its 2s orbital and two electrons in its 2p orbitals. The types of bonding found in carbon compounds arise from various hybrids of the 2s and 2p orbitals. Combination of one 2s and three 2p orbitals 1