Organic Chemistry 6th Edition solutions

Organic Chemistry 6
Predict the products resulting from vigorous oxidation of each compound by H2CrO4. (a) (b) O2N NO2

Organic Chemistry 6
Name the following compounds and ions. C6H5 C6H5 C6H5 1 OH (e) (f) OH Ph (g) O2N (h) !CH (i) (j) 2 CH 1 3O! C C C6H5 H H C6H5 NO2 Cl (a) CH3 (b) (c) NO2 (d) Br OH NO2

Organic Chemistry 6
Draw a structural formula for each compound. (a) 1-Bromo-2-chloro-4-ethylbenzene (b) m- Nitrocumene (c) 4-Chloro-1,2-dimethylbenzene (d) 3,5-Dinitrotoluene (e) 2,4,6-Trinitrotoluene (f) (2S, 4R)-4-Phenyl-2-pentanol (g) p-Cresol (h) Pentachlorophenol (i) 1-Phenylcyclopropanol (j) Triphenylmethane (k)

Organic Chemistry 6
Draw a structural formula for each compound. (a) 1-Nitronaphthalene (b) 1,6-Dichloronaphthalene (c) 9-Bromoanthracene (d) 2-Methylphenanthrene

Organic Chemistry 6
Molecules of 6,69-dinitrobiphenyl-2,29-dicarboxylic acid have no tetrahedral chiral center, and yet they can be resolved to a pair of enantiomers. Account for this chirality. 6,69-Dinitrobiphenyl-2,29- dicarboxylic acid O2N COOH HOOC NO2

Organic Chemistry 6
Following each name is the number of Kekul structures that can be drawn for it. Draw these Kekul structures, and show, using curved arrows, how the fi rst contributing structure for each molecule is converted to the second and so forth. (a) Naphthalene (3) (b) Phenanthrene (5)

Organic Chemistry 6
Each molecule in this problem can be drawn as a hybrid of fi ve contributing structures: two Kekul structures and three that involve creation and separation of unlike charges. Draw these fi ve contributing structures for each molecule. (a) Chlorobenzene (b) Phenol (c) Nitrobenzene

Organic Chemistry 6
Following are structural formulas for furan and pyridine. 1 5 2 34 Furan 1 2 3 6 5 4 Pyridine O N (a) Draw four contributing structures for furan that place a positive charge on oxygen and a negative charge fi rst on carbon 3 of the ring and then on each other carbon of the ring. (b) Draw three contr

Organic Chemistry 6
State the number of 2p orbital electrons in each molecule or ion. (a) (b) (c) (d) 2 2 2 H H H 1 1 H H H H H H H (e) (i) (f) (g) (h) H H H H H H H H H H H H H (j) H H H H H H H H H H H H B H H H H H H H H B!H H H H H H H

Organic Chemistry 6
Which of the molecules and ions given in Problem 21.15 are aromatic according to the Hckel criteria? Which, if planar, would be antiaromatic?

Organic Chemistry 6
Construct MO energy diagrams for the cyclopropenyl cation, radical, and anion. Which of these species is aromatic according to the Hckel criteria?

Organic Chemistry 6
Naphthalene and azulene are constitutional isomers of molecular formula C10H8. Napthalene Azulene 890 Chapter 21 Benzene and the Concept of Aromaticity Naphthalene is a colorless solid with a dipole moment of zero. Azulene is a solid with an intense blue color and a dipole moment of 1.0 D. Account fo

Organic Chemistry 6
Compound A (C9H12) shows prominent peaks in its mass spectrum at m/z 120 and 105. Compound B (also C9H12) shows prominent peaks at m/z 120 and 91. On vigorous oxidation with chromic acid, both compounds give benzoic acid. From this information, deduce the structural formulas of compounds A and B.

Organic Chemistry 6
Compound C shows a molecular ion at m/z 148 and other prominent peaks at m/z 105 and 77. Following are its infrared and 1 H-NMR spectra. (a) Deduce the structural formula of compound C. (b) Account for the appearance of peaks in its mass spectrum at m/z 105 and 77. 10 9 8 7 6 5 4 3 2 1 0 ppm Chemical

Organic Chemistry 6
Following are IR and 1 H-NMR spectra of compound D. The mass spectrum of compound D shows a molecular ion peak at m/z 136, a base peak at m/z 107, and other prominent peaks at m/z 118 and 59. (a) Propose a structural formula for compound D. (b) Propose structural formulas for ions in the mass spectru

Organic Chemistry 6
Compound E (C8H10O2) is a neutral solid. Its mass spectrum shows a molecular ion at m/z 138 and prominent peaks at M-1 and M-17. Following are IR and 1 H-NMR spectra of compound E. Deduce the structure of compound E. 0 100 10 20 30 40 50 90 60 70 80 4000 3600 3200 2800 2400 2000 1800 1600 1400 1200 1

Organic Chemistry 6
Following are 1 H-NMR and 13C-NMR spectral data for compound F (C12H16O). From this information, deduce the structure of compound F. 1 H-NMR 13C-NMR 0.83 (d, 6H) 207.82 50.88 2.11 (m, 1H) 134.24 50.57 2.30 (d, 2H) 129.36 24.43 3.64 (s, 2H) 128.60 22.48 7.227.4 (m, 5H) 126.86

Organic Chemistry 6
Following are 1 H-NMR and 13C-NMR spectral data for compound G (C10H10O). From this information, deduce the structure of compound G. 1 H-NMR 13C-NMR 2.50 (t, 2H) 210.19 126.82 3.05 (t, 2H) 136.64 126.75 3.58 (s, 2H) 133.25 45.02 7.17.3 (m, 4H) 128.14 38.11 127.75 28.34

Organic Chemistry 6
Compound H (C8H6O3) gives a precipitate when treated with hydroxylamine in aqueous ethanol, and a silver mirror when treated with Tollens solution. Following is its 1 H-NMR spectrum. Deduce the structure of compound H. 10 9 8 7 6 5 4 3 2 1 0 ppm Chemical Shift () C8H6O3 Compound H

Organic Chemistry 6
Compound I (C11H14O2) is insoluble in water, aqueous acid, and aqueous NaHCO3 but dissolves readily in 10% Na2CO3 and 10% NaOH. When these alkaline solutions are acidified with 10% HCl, compound I is recovered unchanged. Given this information and its 1 H-NMR spectrum, deduce the structure of compoun

Organic Chemistry 6
Propose a structural formula for compound J (C11H14O3) consistent with its 1 H-NMR and infrared spectra. 10 9 8 7 6 5 4 3 2 1 0 ppm Chemical Shift () C11H14O3 Compound J 3H 2H 3H 2H 2H 2H 0 100 10 20 30 40 50 90 60 70 80 4000 3600 3200 2800 2400 2000 1800 1600 1400 1200 1000 800 600 400 2.5 3 4 5 6 7

Organic Chemistry 6
Propose a structural formula for the analgesic phenacetin, molecular formula C10H13NO2, based on its 1 H-NMR spectrum. 10 9 8 7 6 5 4 3 2 1 0 ppm Chemical Shift () C10H13NO2 Phenacetin 2H 2

Organic Chemistry 6
Compound K, C10H12O2, is insoluble in water, 10% NaOH, and 10% HCl. Given this information and the following 1 H-NMR and 13C-NMR spectral information, deduce the structural formula of Compound K. 1 H-NMR 13C-NMR 2.10 (s, 3H) 206.51 114.17 3.61 (s, 2H) 158.67 55.21 3.77 (s, 3H) 130.33 50.07 6.86 (d, 2

Organic Chemistry 6
Propose a structural formula for each compound given these NMR data. (a) C9H9BrO (b) C8H9NO (c) C9H9NO3 1 H-NMR 13C-NMR 1.39 (t, 3H) 165.73 4.38 (q, 2H) 131.56 7.57 (d, 2H) 131.01 7.90 (d, 2H) 129.84 127.81 61.18 14.18 1 H-NMR 13C-NMR 2.06 (s, 3H) 168.14 7.01 (t, 1H) 139.24 7.30 (m, 2H) 128.51 7.59 (

Organic Chemistry 6
Given here are 1 H-NMR and 13C-NMR spectral data for two compounds. Each shows strong, sharp absorption between 1700 and 1720 cm1, and strong, broad absorption over the region 25003000 cm1. Propose a structural formula for each compound. (a) C10H12O3 (b) C10H10O2 1 H-NMR 13C- NMR 2.49 (t, 2H) 173.89

Organic Chemistry 6
Account for the fact that p-nitrophenol (Ka 7.0 3 1028 ) is a stronger acid than phenol (Ka 1.1 3 1010).

Organic Chemistry 6
Account for the fact that water-insoluble carboxylic acids (pKa 45) dissolve in 10% aqueous sodium bicarbonate (pH 8.5) with the evolution of a gas but that waterinsoluble phenols (pKa 9.510.5) do not dissolve in 10% sodium bicarbonate.

Organic Chemistry 6
Match each compound with its appropriate pKa value. (a) 4-Nitrobenzoic acid, benzoic acid, 4- chlorobenzoic acid pKa 5 4.19, 3.98, and 3.41 (b) Benzoic acid, cyclohexanol, phenol pKa 5 18.0, 9.95, and 4.19 (c) 4-Nitrobenzoic acid, 4-nitrophenol, 4-nitrophenylacetic acid pKa 5 7.15, 3.85, and 3.41

Organic Chemistry 6
Arrange the molecules and ions in each set in order of increasing acidity (from least acidic to most acidic). !OH !OH CH3COOH !OH (a) !OH HCO3 (b) 2 H2O (c) !C#CH !CH2OH

Organic Chemistry 6
Explain the trends in the acidity of phenol and the monofluoro derivatives of phenol. OH pKa 10.0 OH F OH OH F F pKa 8.81 pKa 9.28 pKa 9.81

Organic Chemistry 6
Suppose you wish to determine the inductive effects of a series of functional groups, for example Cl, Br, CN, COOH, and C6H5. Is it best to use a series of ortho-, meta-, or para-substituted phenols? Explain.

Organic Chemistry 6
From each pair, select the stronger base. !O2 OH2 (a) or !O2 HCO3 2 (c) or !O2 !O2 (b) or !O2 CH3COO2

Organic Chemistry 6
Describe a chemical procedure to separate a mixture of benzyl alcohol and o-cresol and to recover each in pure form. CH2OH Benzyl alcohol CH3 OH o-Cresol

Organic Chemistry 6
The compound 2-hydroxypyridine, a derivative of pyridine, is in equilibrium with 2-pyridone. 2- Hydroxypyridine is aromatic. Does 2-pyridone have comparable aromatic character? Explain. OHN 2- Hydroxypyridine ON H 2-Pyridone

Organic Chemistry 6
Write a balanced equation for the oxidation of p-xylene to 1,4-benzenedicarboxylic acid (terephthalic acid) using potassium dichromate in aqueous sulfuric acid. How many milligrams of H2CrO4 are required to oxidize 250 mg of p-xylene to terephthalic acid?

Organic Chemistry 6
Each of the following reactions occurs by a radical chain mechanism. CH3 Br 1 2 1 HBr Toluene heat CH2Br Benzyl bromide CH3 Cl 1 2 1 HCl Toluene heat CH2Cl Benzyl chloride (a) Calculate the heat of reaction, DH0 , in kJ/mol for each reaction. (Consult Appendix 3 for bond dissociation enthalpies.) (b)

Organic Chemistry 6
Following is an equation for iodination of toluene. CH3 I 1 2 1 HI Toluene heat CH2I Benzyl iodide This reaction does not take place. All that happens under experimental conditions for the formation of radicals is initiation to form iodine radicals, I, followed by termination to reform I2. How do you

Organic Chemistry 6
Although most alkanes react with chlorine by a radical chain mechanism when reaction is initiated by light or heat, benzene fails to react under the same conditions. Benzene cannot be converted to chlorobenzene by treatment with chlorine in the presence of light or heat. H Cl 1 2 1 HCl or heat light

Organic Chemistry 6
Following is an equation for hydroperoxidation of cumene. Cumene Cumene hydroperoxide 1 O2 light 9OOH Propose a radical chain mechanism for this reaction. Assume that initiation is by an unspecifi ed radical, R.

Organic Chemistry 6
Para-substituted benzyl halides undergo reaction with methanol by an SN1 mechanism to give a benzyl ether. Account for the following order of reactivity under these conditions. R CH2Br 1 CH3OH R CH2OCH3 1 HBr Rate of SN1 reaction: R CH 5 . .. 3O CH3 H NO2 methanol

Organic Chemistry 6
When warmed in dilute sulfuric acid, 1-phenyl-1,2-propanediol undergoes dehydration and rearrangement to give 2-phenylpropanal. 1-Phenyl-1,2-propanediol (racemic) 2-Phenylpropanal (racemic) H2SO4 1 H2O O H OH OH (a) Propose a mechanism for this example of a pinacol rearrangement (Section 10.7). (b) A

Organic Chemistry 6
In the chemical synthesis of DNA and RNA, hydroxyl groups are normally converted to triphenylmethyl (trityl) ethers to protect the hydroxyl group from reaction with other reagents. tertiary amine RCH2OH 1 Ph3CCl RCH2OCPh3 HCl Triphenylmethyl chloride (Trityl chloride) A triphenylmethyl ether (A trity

Organic Chemistry 6
Use the roadmap you made for problem 20.55 and update it to contain the reactions in the Key Reactions section of this chapter. Because of their highly specifi c nature, do not use reactions 1, 2, and 7 on your roadmap.

Organic Chemistry 6
Write the products of the following sequences of reactions. Refer to your roadmaps to see how the combined reactions allow you to navigate between the different functional groups. Note that you will need your old Chapters 611, Chapters 1518 and Chapter 19 roadmaps along with your new Chapters 2021 ro

Organic Chemistry 6
Using ethylbenzene as the only aromatic starting material, show how to synthesize the following compounds. In addition to ethylbenzene, use any other necessary organic or inorganic chemicals. Any compound already synthesized in one part of this problem may then be used to make any other compound in t

Organic Chemistry 6
Show how to convert 1-phenylpropane into the following compounds. In addition to this starting material, use any necessary inorganic reagents. Any compound synthesized in one part of this problem may be used to make any other compound in the problem. (a) C6H5 (racemic) (racemic) Br (b) C6H5 OH (c) C6

Organic Chemistry 6
Carbinoxamine is a histamine antagonist, specifi cally an H1-antagonist. The maleic acid salt of the levorotatory isomer is sold as the prescription drug Rotoxamine. Br N 1 1 Me Me Me Cl N O N Cl Cl N Me CHO Carbinoxamine (a) Propose a synthesis of carbinoxamine. (Note: Aryl bromides form Grignard re

Organic Chemistry 6
Cromolyn sodium, developed in the 1960s, has been used to prevent allergic reactions primarily affecting the lungs, as for example exercise-induced emphysema. It is thought to block the release of histamine, which prevents the sequence of events leading to swelling, itching, and constriction of bronc

Organic Chemistry 6
The following stereospecifi c synthesis is part of the scheme used by E. J. Corey of Harvard University in the synthesis of erythronolide B, the precursor of the erythromycin antibiotics. In this remarkably simple set of reactions, the relative confi gurations of fi ve chiral centers are established.

Organic Chemistry 6
Following is an outline of one of the fi rst syntheses of the antidepressant fl uoxetine (Prozac). O O HO O F3C OH CH3ONa F3C O O NMe2 NMe2 NMe2 O F3C N Me Cl NMe2 AB C E F O F3C N Me COOH An N-substituted carbamic acid O F3C H N Me Fluoxetine D ? Cl OEt OEt ? ? ? . Problems 901 (a) Propose a reagent

Organic Chemistry 6
Following is a synthesis for the antiarrhythmic drug bidisomide. The symbol Bn is an abbreviation for the benzyl group, C6H5CH2. Cl CN N Bn Cl Cl N CN Cl 1.NaNH2 2. 1.NaNH2 H2SO4 2. N Cl CN N N9Bn AB C O O N Cl NH2 N9Bn D O Cl NH2 N N9H E O Cl NH2 N N Bidisomide ? ? (a) Propose mechanisms for the con

Organic Chemistry 6
A fi nding that opened a route to b-blockers was the discovery that b-blocking activity is retained if an oxygen atom is interposed between the aromatic ring and the side chain. To see this difference, compare the structures of labetalol (Problem 22.55) and propranolol. Thus, alkylation of phenoxide

Organic Chemistry 6
Side effects of propranolol (Problem 21.56) include disturbances of the central nervous system (CNS) such as fatigue, sleep disturbances (including insomnia and nightmares), and depression. Pharmaceutical companies wondered if this drug could be redesigned to eliminate or at least reduce these side e

Organic Chemistry 6
In certain clinical situations, there is need for an injectable b-blocker with a short biological half-life. The clue to development of such a drug was taken from the structure of atenolol, whose corresponding carboxylic acid (the product of hydrolysis of its amide) has no b-blocking activity. Substi

Organic Chemistry 6
Following is an outline of a synthesis of the bronchodilator carbuterol, a beta-2 adrenergic blocker with high selectivity for airway smooth muscle receptors. NO2 O HO O OPh O OPh NH2 NH2 O OPh Br O OPh N O H OPh HN Cl O O OPh HN O O OPh HN NH2 O HN NH2 O N O H HO HN NH2 O N OH H HO HN NH2 O Carbuter

Organic Chemistry 6
Following is a synthesis for albuterol (Proventil), currently one of the most widely used inhalation bronchodilators. HO CHO CH2O NaOH 4-Hydroxybenzaldehyde HO CHO HO A O CHO O B O O C D Albuterol CH39S9CH3 CH3 I DMSO, NaH 1 O O O OH NH HO HO OH NH 5498X_21_ch21_p853- 905.indd 903 12/14/10 4:47:27 PM

Organic Chemistry 6
Estrogens are female sex hormones, the most potent of which is b-estradiol. H3C H H OH H HO -Estradiol In recent years, chemists have focused on designing and synthesizing molecules that bind to estrogen receptors. One target of this research has been nonsteroidal estrogen antagonists, compounds that

Organic Chemistry 6
Following is a synthesis for toremifene, a nonsteroidal estrogen antagonist whose structure is closely related to that of tamoxifen. BnO O 1.THP9O Br, Mg A O B 1.EtONa 2.BrCH2CH2OBn 2.H2O, HCl OH O9THP C BnO OH O9THP D HO O OH E ? H3O1 O F NMe2 Cl HCl O NMe2 Toremifene O NMe2 Cl (a) This synthesis ma