SCHAUM'S outlines Problem Organic Solved Chemistry Fourth Edition 1,806 fully solved problems Concise explanations of al course concepts Information on organic compounds, molecular structure, chemical reactivity and organic reactions, stereochemistry, and spectroscopy and structure USE WITH THESE COURSES Organic Chemistry. Physical Chemistry. Analytical Chemistry Biochemistry. Chemistry Education.Anatomy/Physiology Molecular Biology Herbert Meislich, Ph.D. . Howard Nechamkin, Ph.D. Jacob Sharefkin, Ph.D. . George Hademenos, Ph.D
Preface Eac Schauudertaken toveaclar vi of fityer Organic Chemisyhothe detailed solution of illustrative problems.Such problems make up over8%of the book.the remainder being a concise presentation of the material.Our goal is for students to learn by thinking and solving problems rather han by merely being to rt of a standard text a The second edition has been reorganized by combining chapters to emphasize the similarities of functional groups and reaction types as well as the differences.Thus.polynuclear hydrocarbons are combined with ben ene and aromaticity.Nuc eophilic a up-to-date by including solvent efects CMR spectroscopy.elbration of polymer chemistryand newer concepts of stereochemistry,among other material. JACOB SHAREFKIN GEORGE J.HADEMENOS i●
vii Preface The beginning student in Organic Chemistry is often overwhelmed by facts, concepts, and new language. Each year, textbooks of Organic Chemistry grow in quantity of subject matter and in level of sophistication. This Schaum’s Outline was undertaken to give a clear view of first-year Organic Chemistry through the careful detailed solution of illustrative problems. Such problems make up over 80% of the book, the remainder being a concise presentation of the material. Our goal is for students to learn by thinking and solving problems rather than by merely being told. This book can be used in support of a standard text, as a supplement to a good set of lecture notes, as a review for taking professional examinations, and as a vehicle for self-instruction. The second edition has been reorganized by combining chapters to emphasize the similarities of functional groups and reaction types as well as the differences. Thus, polynuclear hydrocarbons are combined with benzene and aromaticity. Nucleophilic aromatic displacement is merged with aromatic substitution. Sulfonic acids are in the same chapter with carboxylic acids and their derivatives, and carbanion condensations are in a separate new chapter. Sulfur compounds are discussed with their oxygen analogs. This edition has also been brought up-to-date by including solvent effects, CMR spectroscopy, an elaboration of polymer chemistry, and newer concepts of stereochemistry, among other material. HERBERT MEISLICH HOWARD NECHAMKIN JACOB SHAREFKIN GEORGE J. HADEMENOS
Contents CHAPTER 1 Structure and Properties of Organic Compounds CHAPTER2 Bonding and Molecular Structure CHAPTER3 Chemical Reactivity and Organic Reactions 31 CHAPTER 4 Alkanes 50 CHAPTER5 Stereochemistry 69 CHAPTER 6 Alkenes 87 CHAPTER 7 Alkyl Halides 118 CHAPTER8 Alkynes and Dienes 140 CHAPTER 9 Cyclic Hydrocarbons 162 CHAPTER 10 Benzene and Polynuclear Aromatic Compounds 189 CHAPTER 11 Aromatic Substitution;Arenes 205 CHAPTER 12 Spectroscopy and Structure CHAPTER 13 Alcohols and Thiols 6 CHAPTER 14 Ethers,Epoxides,Glycols,and Thioethers 278 CHAPTER 15 Carbonyl Compounds:Aldehydes and Ketones CHAPTER 16 Carboxylic Acids and their Derivatives CHAPTER 17 Carbanion-Enolates and Enols 373 CHAPTER 18 Amines CHAPTER 19 Phenolic Compounds 430 CHAPTER 20 Aromatic Heterocyclic Compounds 448 Index 464 ix●
ix Contents CHAPTER 1 Structure and Properties of Organic Compounds 1 CHAPTER 2 Bonding and Molecular Structure 13 CHAPTER 3 Chemical Reactivity and Organic Reactions 31 CHAPTER 4 Alkanes 50 CHAPTER 5 Stereochemistry 69 CHAPTER 6 Alkenes 87 CHAPTER 7 Alkyl Halides 118 CHAPTER 8 Alkynes and Dienes 140 CHAPTER 9 Cyclic Hydrocarbons 162 CHAPTER 10 Benzene and Polynuclear Aromatic Compounds 189 CHAPTER 11 Aromatic Substitution;Arenes 205 CHAPTER 12 Spectroscopy and Structure 230 CHAPTER 13 Alcohols and Thiols 256 CHAPTER 14 Ethers, Epoxides, Glycols, and Thioethers 278 CHAPTER 15 Carbonyl Compounds:Aldehydes and Ketones 302 CHAPTER 16 Carboxylic Acids and their Derivatives 331 CHAPTER 17 Carbanion-Enolates and Enols 373 CHAPTER 18 Amines 400 CHAPTER 19 Phenolic Compounds 430 CHAPTER 20 Aromatic Heterocyclic Compounds 448 Index 464
CHAPTER 1 Structure and Properties of Organic Compounds 1.1 Carbon Compounds Organic chemistry is the study of carbon (C)compounds,all of which have covalent bonds.Carbon atoms can bond to each other t T网e3光里 with double bonds and triple bonds are shown in Fig.1.1(e).Cyclic compounds having at least one atom in the ring other than C(a heteroatom)are called heterocyclics.Fig.1.1(f).The heteroatoms are usually oxygen (O),nitrogen(N).or sulfur(S). Problem 11 Why are there so many compounds that contain carbon? Bonds between C's are covalent and strong,so that C's can form long chains and rings,both of which may ssoCSsesnmeRmntaikthAnkraioncRe Problem1.2 Compare and contrast the properties of ionic and covalent compounds. Ionic compounds are generally inorganic,have high melting and boiling points due to the strong electro Covalent compounds,on the other hand,are commonly organic:have relatively low melting and boiling points because of weak intermolecular forces;are soluble in organic solvents and insoluble in water:burn read ily and are thus susceptible to oxidation because they are less stable to heat,usually decomposing at tempera complex, ding higher
CHAPTER 1 1 Structure and Properties of Organic Compounds 1.1 Carbon Compounds Organic chemistry is the study of carbon (C) compounds, all of which have covalent bonds. Carbon atoms can bond to each other to form open-chain compounds, Fig. 1.1(a), or cyclic (ring) compounds, Fig. 1.1(c). Both types can also have branches of C atoms, Fig. 1.1(b) and (d). Saturated compounds have C atoms bonded to each other by single bonds, C—C; unsaturated compounds have C’s joined by multiple bonds. Examples with double bonds and triple bonds are shown in Fig. 1.1(e). Cyclic compounds having at least one atom in the ring other than C (a heteroatom) are called heterocyclics, Fig. 1.1(f). The heteroatoms are usually oxygen (O), nitrogen (N), or sulfur (S). Problem 1.1 Why are there so many compounds that contain carbon? Bonds between C’s are covalent and strong, so that C’s can form long chains and rings, both of which may have branches. C’s can bond to almost every element in the periodic table. Also, the number of isomers increases as the organic molecules become more complex. Problem 1.2 Compare and contrast the properties of ionic and covalent compounds. Ionic compounds are generally inorganic, have high melting and boiling points due to the strong electrostatic forces attracting the oppositely charged ions, are soluble in water and insoluble in organic solvents, are hard to burn, and involve reactions that are rapid and simple. Also, bonds between like elements are rare, with isomerism being unusual. Covalent compounds, on the other hand, are commonly organic; have relatively low melting and boiling points because of weak intermolecular forces; are soluble in organic solvents and insoluble in water; burn readily and are thus susceptible to oxidation because they are less stable to heat, usually decomposing at temperatures above 700ºC; and involve reactions that are slow and complex, often needing higher temperatures and/ or catalysts, yielding mixtures of products. Also, bonds between carbon atoms are typical, with isomerism being common
2● CHAPTER 1 Structure and Properties of Organic Compounds HHHH HH H-C-C-C-C-H H- HH H HHHH H H H H n8c (c) (d) HH Hc-H H H-C=C-H H H Ethene(Ethylene) Cyclopentene have double bonds (e) Figure 1.1 1.2 Lewis Structural Formulas Molecular formulas merely include the kinds of atom and the each in )St e number of electrons are included.the latter are called Lewis (electron-dot)structures see Fig.Covalences of the common elements-the numbers of covalent bonds they usually form-are given in Table 1.1:these help us to wis structures.Multicovalent clements such a C.O.and N may have multiple bonds,as shown in om to dens they are atta CH.CH(CH . Problem 1.3 (a)Are the covalences and group numbers(numbers of valence electrons)of the elements in 1.1 relate ()Why aren Grup lements incluhrone d in (a)Yes.For the elements in Groups 4 through 7,Covalence=8-(Group number). (b)No.The elements in Groups 4 through 7 do attain the octet,but the elements in Groups 2 and 3 have less octet of ence clectrons.d andr enods.suandmay acheverea (c)They fom dson c rather than covalent bond Most c th by the C atom.The spatial relationship is indicated as in Fig.1.2(a)(Newman projection)or in Fig.1.2(b) xcept for ethene,which is planar,and ethyne,which is linear,the structures in Fig.1.1 are ulas ur s Thi of isomerism is exemplified by isobutane and n-butane Fig1.1(a)and (The number of isomers increases as the number of atoms in the organic molecule increases
1.2 Lewis Structural Formulas Molecular formulas merely include the kinds of atoms and the number of each in a molecule (as C4H10 for butane). Structural formulas show the arrangement of atoms in a molecule (see Fig. 1.1). When unshared electrons are included, the latter are called Lewis (electron-dot) structures [see Fig. 1-1(f)]. Covalences of the common elements—the numbers of covalent bonds they usually form—are given in Table 1.1; these help us to write Lewis structures. Multicovalent elements such as C, O, and N may have multiple bonds, as shown in Table 1.2. In condensed structural formulas, all H’s and branched groups are written immediately after the C atom to which they are attached. Thus, the condensed formula for isobutane [Fig. 1-1(b)] is CH3CH(CH3)2. Problem 1.3 (a) Are the covalences and group numbers (numbers of valence electrons) of the elements in Table 1.1 related? (b) Do all the elements in Table 1.1 attain an octet of valence electrons in their bonded states? (c) Why aren’t Group 1 elements included in Table 1.1? (a) Yes. For the elements in Groups 4 through 7, Covalence 8 (Group number). (b) No. The elements in Groups 4 through 7 do attain the octet, but the elements in Groups 2 and 3 have less than an octet. (The elements in the third and higher periods, such as Si, S, and P, may achieve more than an octet of valence electrons.) (c) They form ionic rather than covalent bonds. (The heavier elements in Groups 2 and 3 also form mainly ionic bonds. In general, as one proceeds down a group in the periodic table, ionic bonding is preferred.) Most carbon-containing molecules are three-dimensional. In methane, the bonds of C make equal angles of 109.5º with each other, and each of the four H’s is at a vertex of a regular tetrahedron whose center is occupied by the C atom. The spatial relationship is indicated as in Fig. 1.2(a) (Newman projection) or in Fig. 1.2(b) (“wedge” projection). Except for ethene, which is planar, and ethyne, which is linear, the structures in Fig. 1.1 are all three-dimensional. Organic compounds show a widespread occurrence of isomers, which are compounds having the same molecular formula but different structural formulas, and therefore possessing different properties. This phenomenon of isomerism is exemplified by isobutane and n-butane [Fig. 1.1(a) and (b)]. The number of isomers increases as the number of atoms in the organic molecule increases. 2 CHAPTER 1 Structure and Properties of Organic Compounds H C C H H CC C C H H HH O H H H H n-Butane unbranched, open-chain (a) Isobutane branched, open-chain (b) Cyclopropane unbranched, cyclic (c) Methylcyclopropane branched, cyclic (d) Ethene (Ethylene) have double bonds Cyclopentene (e) Ethyne (Acetylene) has a triple bond Ethylene oxide heterocyclic (f ) H H H C H H C H H C H H C H H H C C H C C C H H H H H H H H C H H H H H C H H H H H HH H C C H H H H H H H C C C C C C H Figure 1.1