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1 Million+ Step-by-step solutionsmath books Q:A single organic product was isolatedA single organic product was isolated after Birch reduction of p-xylene. Suggest a reasonable structure for this substance.Q:The reaction of N-bromosuccinimideThe reaction of N-bromosuccinimide with the following compounds has been reported in the chemical literature. Each compound yields a single product in 95% yield. Identify the product formed from each starting material.
(a) p-tert-Butylatoluene
(b) 4-Methyl-3-nitroanisoleQ:Chromic acid oxidation of 4-tert-butyl-1Chromic acid oxidation of 4-tert-butyl-1, 2-dimethylbenzene yielded a single compound having the molecular formula C12H14O4. What was this compound?Q:Give the structure of the principal organic product formed onGive the structure of the principal organic product formed on reaction of benzyl bromide with each of the following reagents:
(a) Sodium ethoxide
(d) Sodium hydrogen sulfide
(b) Potassium tert-butoxide
(e) Sodium iodide (in acetone)
(c) Sodium azideQ:Both 1, 2-dihydronaphthalene and 1Both 1, 2-dihydronaphthalene and 1, 4-dihydronaphthalene may be selectively hydrogenated to 1, 2, 3, 4-tetrahydronaphthalene.Q:Each of the following reactions has been reported in the 5691Each of the following reactions has been reported in the chemical literature and gives a single organic product in high yield. Write the structure of the product for each reaction.
(a) 2-Phenylpropene + hydrogen chloride
(b) 2-Phenylpropene treated with diborane in tetrahydrofuran followed by oxidation with basic hydrogen peroxide
(c) Styrene + bromine in aqueous solution
(d) Styrene + peroxybenzoic acid (two organic products in this reaction; identify both by writing a balanced equation.)Q:Both cyclooctatetraene and styrene have the molecularBoth cyclooctatetraene and styrene have the molecular formula C8H8 and undergo combustion according to the equation
C8H8 + 10O2 → 8CO2 + 4H2O
The measured heats of combustion are 4393 and 4543 kJ/mol (1050 and 1086 kcal/mol). Which heat of combustion belongs to which compound?Q:One of the chemical propertiesOne of the chemical properties that make cyclobutadiene difficult to isolate is that it reacts readily with itself to give a dimer:Q:Represent the electron distribution amongRepresent the electron distribution among the π orbitals in
(a) [10]-Annulene
(b) [12]-AnnuleneQ:What does a comparison of the heats of combustionWhat does a comparison of the heats of combustion of benzene (3265 kJ/mol; 781 kcal/mol), cyclooctatetraene (4543 kJ/mol; 1086 kcal/mol), [16]-annulene (9121 kJ/mol; 2182 kcal/mol), and [18]-annulene (9806 kJ/mol; 2346 kcal/mol) reveal?Q:Write resonance structures for tropyliumWrite resonance structures for tropylium cation sufficient to show the delocalization of the positive charge over all seven carbons.Q:Write resonance structures for cyclopentadienideWrite resonance structures for cyclopentadienide anion sufficient to show the delocalization of the negative charge over all five carbons.Q:A standard method for the preparationA standard method for the preparation of sodium cyclopentadienide (C5H5Na) is by reaction of cyclopentadiene with a solution of sodium amide in liquid ammonia. Write a balanced equation for this reaction.Q:Is either of the followingIs either of the following ions aromatic?Q:Unlike quinoline and isoquinolineUnlike quinoline and isoquinoline, which are of comparable stability, the compounds indole and isoindole are quite different from each other. Which one is more stable? Explain the reason for your choice.Q:Can you deduce the structuralCan you deduce the structural formulas of benzoxazole and benzothiazole?Q:Imidazole is a much stronger base than pyrroleImidazole is a much stronger base than pyrrole. Predict which nitrogen is protonated when imidazole reacts with an acid, and write a structural formula for the species formed.Q:Write structural formulas and give the IUPAC names for all theWrite structural formulas and give the IUPAC names for all the isomers of C6H5C4H9 that contain a monosubstituted benzene ring.Q:Write a structural formula correspondingWrite a structural formula corresponding to each of the following:
(a) Allylbenzene
(g) 2-Nitrobenzenecarboxylic acid
(b) (E)-1-Phenyl-1-butene
(h) p-Diisopropylbenzene
(c) (Z)-2-Phenyl-2-butene
(i) 2, 4, 6-Tribromoaniline
(d) (R)-1-Phenylethanol
(j) m-Nitroacetophenone
(e) o-Chlorobenzyl alcohol
(k) 4-Bromo-3-ethylstyrene
(f) p-ChloropreneQ:Using numerical locants and the names in Table 11.1Using numerical locants and the names in Table 11.1 as a guide, give an acceptable IUPAC name for each of the following compoundsQ:Write structural formulas and give acceptable names for all the 5706Write structural formulas and give acceptable names for all the isomeric
(a) Nitrotoluenes
(d) Tetrafluorobenzenes
(b) Dichlorobenzoic acids
(e) Naphthalene carboxylic acids
(c) Tribromophenols
(f) BromoanthracenesQ:Mesitylene (1, 3, 5-trimethylbenzene)Mesitylene (1, 3, 5-trimethylbenzene) is the most stable of the trimethylbenzene isomers. Can you think of a reason why? Which isomer do you think is the least stable? Make a molecular model of each isomer and compare their calculated strain energies with your predictions. Do space filling models support your explanation?Q:Which one of the dichlorobenzene isomersWhich one of the dichlorobenzene isomers does not have a dipole moment? Which one has the largest dipole moment? Compare your answers with the dipole moments calculated using the molecular-modeling software in Learning by Modeling.Q:Identify the longest and the shortest carbonIdentify the longest and the shortest carbon–carbon bonds in styrene. Make reasonable estimates of their bond distances and compare them to the distances in a molecular model.Q:The resonance form shownThe resonance form shown is not the most stable one for the compound indicated. Write the most stable resonance form.Q:Each of the following may be representedEach of the following may be represented by at least one alternative resonance structure in which all the six-membered rings correspond to Kekule forms of benzene. Write such a resonance form for each.Q:Give the structure of the expected product from the reactionGive the structure of the expected product from the reaction of isopropyl benzene with
(a) Hydrogen (3 mol), Pt
(b) Sodium and ethanol in liquid ammonia
(c) Sodium dichromate, water, sulfuric acid, heat
(d) N-Bromosuccinimide in CCl4, heat, benzoyl peroxide
(e) The product of part (d) treated with sodium ethoxide in ethanolQ:Each of the following reactions has been described in the 5713Each of the following reactions has been described in the chemical literature and gives a single organic product in good yield. Identify the product of each reaction.Q:A certain compound A, when treatedA certain compound A, when treated with N-bromosuccinimide and benzoyl peroxide under photochemical conditions in refluxing carbon tetrachloride, gave 3, 4, 5-tribromobenzyl bromide in excellent yield. Deduce the structure of compound A.Q:A compound was obtained from a naturalA compound was obtained from a natural product and had the molecular formula C14H20O3. It contained three methoxy (─OCH3) groups and a ─CH2CHoeC (CH3)2 substituent. Oxidation with either chromic acid or potassium permanganate gave 2, 3, 5-trimethoxybenzoic acid. What is the structure of the compound?Q:Hydroboration–oxidation of (E)-2-( p-anisyl)-2-buteneHydroboration–oxidation of (E)-2-( p-anisyl)-2-butene yielded an alcohol A, mp 60°C, in 72% yield. When the same reaction was performed on the Z alkene, an isomeric liquid alcohol B was obtained in 77% yield. Suggest reasonable structures for A and B, and describe the relationship between themQ:Dehydrohalogenation of the diastereomericDehydrohalogenation of the diastereomeric forms of 1-chloro-1, 2-diphenylpropane is stereospecific. One diastereomer yields (E)-1, 2-diphenylpropene, and the other yields the Z isomer. Which diastereomer yields which alkene? Why?Q:Suggest reagents suitable for carrying outSuggest reagents suitable for carrying out each of the following conversions. In most cases more than one synthetic operation will be necessaryQ:The relative rates of reaction of ethaneThe relative rates of reaction of ethane, toluene, and ethylbenzene with bromine atoms have been measured. The most reactive hydrocarbon undergoes hydrogen atom abstraction a million times faster than does the least reactive one. Arrange these hydrocarbons in order of decreasing reactivity.Q:Write the principal resonance structuresWrite the principal resonance structures of o-methylbenzyl cation and m-methylbenzyl cation. Which one has a tertiary carbocation as a contributing resonance form?Q:The same anion is formed by lossThe same anion is formed by loss of the most acidic proton from 1-methyl-1, 3-cyclopentadiene as from 5-methyl-1, 3-cyclopentadiene. Explain.Q:There are two different tetramethyl derivativesThere are two different tetramethyl derivatives of cyclooctatetraene that have methyl groups on four adjacent carbon atoms. They are both completely conjugated and are not stereoisomers. Write their structures.Q:Evaluate each of the following processesEvaluate each of the following processes applied to cyclooctatetraene, and decide whether the species formed is aromatic or not.
(a) Addition of one more π electron, to give C8H8─
(b) Addition of two more π electrons, to give C8H8 2─
(c) Removal of one π electron, to give C8H8 +
(d) Removal of two π electrons, to give C8H8 2+Q:Evaluate each of the followingEvaluate each of the following processes applied to cyclononatetraene, and decide whether the species formed is aromatic or not:
(a) Addition of one more π electron, to give C9H10─
(b) Addition of two more π electrons, to give C9H10 2─
(c) Loss of H+ from the sp3-hybridized carbon
(d) Loss of H+ from one of the sp2-hybridized carbonsQ:From among the molecules and ions shownFrom among the molecules and ions shown, all of which are based on cycloundecapentaene, identify those which satisfy the criteria for aromaticity as prescribed by Hackle’s rule.Q:(a)Figure 11.16 is an electrostatic potential(a)Figure 11.16 is an electrostatic potential map of calicene, so named because its shape resembles a chalice (calix is the Latin word for “cup”). Both the electrostatic potential map and its calculated dipole moment (μ = 4.3 D) indicate that calicene is an unusually polar hydrocarbon. Which of the dipolar resonance forms, A or B, better corresponds to the electron distribution in the molecule? Why is this resonance form more important than the other?Q:Classify each of the following heterocyclicClassify each of the following heterocyclic molecules as aromatic or not, according to Hackle’s rule:Q:Pellagra is a disease caused by a deficiencyPellagra is a disease caused by a deficiency of niacin (C6H5NO2) in the diet. Niacin can be synthesized in the laboratory by the side-chain oxidation of 3- methylpyridine with chromic acid or potassium permanganate. Suggest a reasonable structure for niacin.Q:Nitroxoline is the generic nameNitroxoline is the generic name by which 5-nitro-8-hydroxyquinoline is sold as an antibacterial drug. Write its structural formula.Q:Acridine is a heterocyclic aromatic compoundAcridine is a heterocyclic aromatic compound obtained from coal tar that is used in the synthesis of dyes. The molecular formula of Acridine is C13H9N, and its ring system is analogous to that of anthracene except that one CH group has been replaced by N. The two most stable resonance structures of Acridine are equivalent to each other, and both contain a pyridine-like structural unit. Write a structural formula for Acridine.Q:Nitration of 1, 4-dimethylbenzene (p-xylene)Nitration of 1, 4-dimethylbenzene (p-xylene) gives a single product having the molecular formula C8H9NO2 in high yield. What is this product?Q:The compounds benzyl chloride (C6H5CH2Cl)The compounds benzyl chloride (C6H5CH2Cl), (dichloromethyl) benzene (C6H5CHCl2), and (trichloroethylene benzene (C6H5CCl3) all undergo nitration more slowly than benzene, the proportion of m-nitro-substituted product is 4% in one, 34% in another, and 64% in another. Classify the substituents ─CH2Cl, ─CHCl2, and ─CCl3 according to each one’s effect on rate and regioselectivity in electrophilic aromatic substitutionQ:Write structural formulas for the cyclohexadienyWrite structural formulas for the cyclohexadienyl cations formed from aniline (C6H5NH2) during
(a) Ortho bromination (four resonance structures)
(b) Meta bromination (three resonance structures)
(c) Para bromination (four resonance structures)Q:Treatment of biphenyl (see Section 11.7

Treatment of biphenyl (see Section 11.7 to remind yourself of its structure) with a mixture of nitric acid and sulfuric acid gave two principal products both having the molecular formula C12H9NO2. What are these two products? Explain.

Q:Treatment of biphenylTreatment of biphenyl (see Section 11.7 to remind yourself of its structure) with a mixture of nitric acid and sulfuric acid gave two principal products both having the molecular formula C12H9NO2. What are these two products?Q:Would you expect the substituentWould you expect the substituent ─N (CH3)3 to more closely resemble ─N (CH3)2 or ─NO2 in its effect on rate and regioselectivity in electrophilic aromatic substitution? Why?Q:Reaction of chlorobenzene with 4-chlorobenzylReaction of chlorobenzene with 4-chlorobenzyl chloride and aluminum chloride gave a mixture of two products in good yield (76%). What were these two products?Q:Write the structure of the principal organic product obtained onWrite the structure of the principal organic product obtained on nitration of each of the following:
(a) p-Methyl benzoic acid
(d) p-Methoxyacetophenone
(b) m-Dichlorobenzene
(e) p-Methyl anisole
(c) m-Dinitrobenzene
(f) 2, 6-Dibromoanisole
Q:Write chemical equations showing how you couldWrite chemical equations showing how you could prepare m-bromonitrobenzene as the principal organic product, starting with benzene and using any necessary organic or inorganic reagents. How could you prepare p-bromonitrobenzene?Q:Suggest an efficient synthesis of m-nitrobenzoicSuggest an efficient synthesis of m-nitrobenzoic acid from toluene.Q:Suffocation of naphthalene is reversibleSuffocation of naphthalene is reversible at elevated temperature. A different isomer of naphthalenesulfonic acid is the major product at 160°C than is the case at 0°C. Which isomer is the product of kinetic control? Which one is formed under conditions of thermodynamic control? Can you think of a reason why one isomer is more stable than the other? (Hint: Build space-filling models of both isomers.Q:On being heated with sulfur trioxideOn being heated with sulfur trioxide in sulfuric acid, 1, 2, 4, 5-tetramethylbenzene was converted to a product of molecular formula C10H14O3S in 94% yield. Suggest a reasonable structure for this product.Q:When benzene is prepared from coal tar,When benzene is prepared from coal tar, it is contaminated with thiophene, from which it cannot be separated by distillation because of very similar boiling points. Shaking a mixture of benzene and thiophene with sulfuric acid causes sulfonation of the thiophene ring but leaves benzene untouched. The sulfonation product of thiophene dissolves in the sulfuric acid layer, from which the benzene layer is separated; the benzene layer is then washed with water and distilled. Give the structure of the sulfonation product of thiophene.Q:Give reagents suitable for carryingGive reagents suitable for carrying out each of the following reactions, and write the major organic products. If an ortho, para mixture is expected, show both. If the Meta isomer is the expected major product, write only that isomer.
(a) Nitration of benzene
(b) Nitration of the product of part (a)
(c) Bromination of toluene
(d) Bromination of (trifluoromethyl) benzene
(e) Sulfonation of anisole
(f) Sulfonation of acetanilide(C6H5NHCCH3)
(g) Chlorination of bromobenzene
(h) Friedel–Crafts alkylation of anisole with benzyl chloride
(i) Friedel–Crafts acylations of benzene with benzoyl chloride
(j) Nitration of the product from part (i)
(k) Clemmensen reduction of the product from part (i)
(l) Wolff–Kishner reduction of the product from part (i)Q:Write a structural formula for the most stable cyclohexadienyl cation intermediate formedWrite a structural formula for the most stable cyclohexadienyl cation intermediate formed in each of the following reactions. Is this intermediate more or less stable than the one formed by electrophilic attack on benzene?
(a) Bromination of p-xylene
(b) Chlorination of m-xylene
(c) Nitration of acetophenone
(d) Friedel–Crafts acylation of anisole withCH3CCI
(e) Nitration of isopropyl benzene
(f) Bromination of nitrobenzene
(g) Sulfonation of furan
(h) Bromination of pyridineQ:In each of the following pairs of compounds choose which oneIn each of the following pairs of compounds choose which one will react faster with the indicated reagent, and write a chemical equation for the faster reaction:
(a) Toluene or chlorobenzene with a mixture of nitric acid and sulfuric acid
(b) Fluorobenzene or (trifluoromethyl) benzene with benzyl chloride and aluminum chloride
(c) Methyl benzoate (C6H5COCH3) or phenyl acetate (C6H5COCH3) with bromine in acetic acid
(d) Acetanilide (C6H5COCH3) or nitrobenzene with sulfur trioxide in sulfuric acid
(e) p-Dimethylbenzene (p-xylene) or p-di-tert-butyl benzene with acetyl chloride and aluminum chloride
(f) Benzophenone (C6H5CC6H5) or biphenyl (C6H5-C6H5) with chlorine and iron (III) chlorideQ:Arrange the following five compounds in orderArrange the following five compounds in order of decreasing rate of bromination: benzene, toluene, o-xylene, m-xylene, 1, 3, 5-trimethylbenzene (the relative rates are 2 x 107, 5 x 104, 5 x 102, 60, and 1).Q:Each of the following reactions has been carried out underEach of the following reactions has been carried out under conditions such that disubstitution or trisubstitution occurred. Identify the principal organic product in each case.
(a) Nitration of p-chlorobenzoic acid (dinitration)
(b) Bromination of aniline (tribromination)
(c) Bromination of o-aminoacetophenone (dibromination)
(d) Nitration of benzoic acid (dinitration)
(e) Bromination of p-nitro phenol (dibromination)
(f) Reaction of biphenyl with tert-butyl chloride and iron (III) chloride (dialkylation)
(g) Sulfonation of phenol (disulfonation)Q:Write equations showing how you could prepareWrite equations showing how you could prepare each of the following from benzene or toluene and any necessary organic or inorganic reagents. If an ortho, para mixture is formed in any step of your synthesis, assume that you can separate the two isomers.
(a) Isopropylbenzene
(j) 1-Bromo-2,
4-dinitrobenzene
(b) p-Isopropylbenzenesulfonic acid
(k) 3-Bromo-5-nitrobenzoic acid
(c) 2-Bromo-2-phenylpropane
(l) 2-Bromo-4-nitrobenzoic acid
(d) 4-tert-Butyl-2-nitrotoluene
(m) Diphenylmethane
(e) m-Chloroacetophenone
(n) 1-Phenyloctane
(f) p-Chloroacetophenone
(o) 1-Phenyl-1-octene
(g) 3-Bromo-4-methylacetophenone
(p) 1-Phenyl-1-octyne
(h) 2-Bromo-4-ethyltoluene
(q) 1, 4-Di-tert-butyl-1,
4-cyclohexadiene
(i) 1-Bromo-3-nitrobenzeneQ:Write equations showing how youWrite equations showing how you could prepare each of the following from anisole and any necessary organic or inorganic reagents. If an ortho, para mixture is formed in any step of your synthesis, assume that you can separate the two isomers.
(a) p-Methoxybenzenesulfonic acid (c) 4-Bromo-2-nitroanisole (b) 2-Bromo-4-nitroanisole (d) p-MethoxystyreneQ:How many products are capableHow many products are capable of being formed from toluene in each of the following reactions?
(a) Mononitration (HNO3, H2SO4, 40°C).
(b) Dinitration (HNO3, H2SO4, 80°C).
(c) Trinitration (HNO3, H2SO4, 110°C). The explosive TNT (trinitrotoluene) is the major product obtained on trinitration of toluene. Which trinitrotoluene isomer is TNT?Q:Friedel–Crafts acylationFriedel–Crafts acylation of the individual isomers of xylene with acetyl chloride and aluminum chloride yields a single product, different for each xylene isomer, in high yield in each case. Write the structures of the products of acetylation of o-, m-, and p-xylene.Q:In an attempt to prepare propylbenzeneIn an attempt to prepare propylbenzene, a chemist alkylated benzene with 1-chloropropane and aluminum chloride. However, two isomeric hydrocarbons were obtained in a ratio of 2:1, the desired propylbenzene being the minor component. What do you think was the major product? How did it arise?Q:Reaction of benzanilide (C6H5NHCC6H5)Reaction of benzanilide (C6H5NHCC6H5) with chlorine in acetic acid yields a mixture of two monochloro derivatives formed by electrophilic aromatic substitution. Suggest reasonable structures for these two isomers.Q:Each of the followingEach of the following reactions has been reported in the chemical literature and gives a predominance of a single product in synthetically acceptable yield. Write the structure of the product. Only monosubstitution is involved in each case, unless otherwise indicated.Q:What combination of acyl chlorideWhat combination of acyl chloride or acid anhydride and arene would you choose to prepare each of the following compounds by a Friedel–Crafts acylation reaction?Q:Suggest a suitable series of reactionsSuggest a suitable series of reactions for carrying out each of the following synthetic transformations:Q:A standard synthetic sequence for buildingA standard synthetic sequence for building a six-membered cyclic ketone onto an existing aromatic ring is shown in outline as follows. Specify the reagents necessary for each step.Q:Each of the compounds indicated undergoesEach of the compounds indicated undergoes an intermolecular Friedel–Crafts acylation reaction to yield a cyclic ketone. Write the structure of the expected product in each case.Q:The partial rate factors for chlorinationThe partial rate factors for chlorination of biphenyl are as shown.Q:Partial rate factors may be usedPartial rate factors may be used to estimate product distributions in disubstituted benzene derivatives. The reactivity of a particular position in o-bromotoluene, for example, is given by the product of the partial rate factors for the corresponding position in toluene and bromobenzene. On the basis of the partial rate factor data given here for Friedel–Crafts acylation, predict the major product of the reaction of o-bromotoluene with acetyl chloride and aluminum chloride.Q:When 2-isopropyl-1,3,5-trimethylbenzeneWhen 2-isopropyl-1,3,5-trimethylbenzene is heated with aluminum chloride (trace of HCl present) at 50°C, the major material present after 4 h is 1-isopropyl-2,4,5-trimethylbenzene. Suggest a reasonable mechanism for this isomerization.Q:When a dilute solution of 6-phenylhexanoylWhen a dilute solution of 6-phenylhexanoyl chloride in carbon disulfide was slowly added (over a period of 8 days!) to a suspension of aluminum chloride in the same solvent, it yielded a product A (C12H14O) in 67% yield. Oxidation of A gave benzene-1, 2-dicarboxylic acid.Q:Write a reasonable mechanismWrite a reasonable mechanism for the formation of cyclohexylbenzene from the reaction of benzene, cyclohexene, and sulfuric acid.Q:Reaction of hex methylbenzene with methylReaction of hex methylbenzene with methyl chloride and aluminum chloride gave a salt A, which, on being treated with aqueous sodium bicarbonate solution, yielded compound B. Suggest a mechanism for the conversion of hex methylbenzene to B by correctly inferring the structure of A.Q:The synthesis of compound C was achievedThe synthesis of compound C was achieved by using compounds A and B as the sources of all carbon atoms. Suggest a synthetic sequence involving no more than three steps by which A and B may be converted to C.Q:When styrene is refluxed with aqueousWhen styrene is refluxed with aqueous sulfuric acid, two “styrene dimers” are formed as the major products. One of these styrene dimers is 1, 3-diphenyl-1-butene; the other is 1-methyl- 3-phenylindan. Suggest a reasonable mechanism for the formation of each of these compounds.Q:Treatment of the alcohol whose structureTreatment of the alcohol whose structure is shown here with sulfuric acid gave as the major organic product a tricycles hydrocarbon of molecular formula C16H16. Suggest a reasonable structure for this hydrocarbon.Q:Outline a synthesis of 1-phenylcyclohexeneOutline a synthesis of 1-phenylcyclohexene from benzene and cyclohexene.Q:The reaction shown gives a single productThe reaction shown gives a single product in 88% yield. What is that product?Q:In the simplest molecular orbital treatmentIn the simplest molecular orbital treatment of conjugated systems, it is assumed that the π system does not interact with the framework of σ bonds. When this MO method was used to calculate the charge distribution in cyclohexadienyl cation, it gave the results indicated. How does the charge at each carbon compare with that deduced by examining the most stable resonance structures for cyclohexadienyl cation?Q:Succinct anhydride, the structureSuccinct anhydride, the structure of which is shown, is a cyclic anhydride often used in Friedel-Crafts acylations. Give the structure of the product obtained when benzene is acylated with succinct anhydride in the presence of aluminum chloride.Q:Using benzene and any necessary organicUsing benzene and any necessary organic or inorganic reagents, suggest efficient syntheses of
(a) Isobutyl benzene, C6H5CH2CH (CH3)2
(b) Neopentylbenzene, C6H5CH2C (CH3)3Q:The partial rate factors for nitrationThe partial rate factors for nitration of tert-butyl benzene are as shown.Q:Most of the NMR spectra in this textMost of the NMR spectra in this text were recorded on a spectrometer having field strength of 4.7 T (200 MHz for 1H). The first generation of widely used NMR spectrometers was 60-MHz instruments. What was the magnetic field strength of these earlier spectrometers?Q:What will be the 13C frequency settingWhat will be the 13C frequency setting of an NMR spectrometer that operates at 100 MHz for protons?Q:The 1H NMR signal for bromoform (CHBr3)The 1H NMR signal for bromoform (CHBr3) appears at 2065 Hz when recorded on a 300-MHz NMR spectrometer. (a) What is the chemical shift of this proton? (b) Is the proton in CHBr3 more shielded or less shielded than the proton in CHCl3?Q:There is a difference of 4.6 ppm in the 1HThere is a difference of 4.6 ppm in the 1H chemical shifts of CHCl3 and CH3CCl3. What is the chemical shift for the protons in CH3CCl3? Explain your reasoningQ:The 200-MHz 1H NMR spectrum of 1The 200-MHz 1H NMR spectrum of 1, 4-dimethylbenzene looks exactly like that of CH3OCH2CN except the chemical shifts of the two peaks are δ 2.2 ppm and δ 7.0 ppm. Assign the peaks to the appropriate protons of 1, 4- dimethylbenzene.Q:How many signals would you expectHow many signals would you expect to find in the 1H NMR spectrum of each of the following compounds?M
(a) 1-Bromobutane
(c) Butane
(b) 1-Butanol
(d) 1, 4-Dibromobutane
(e) 2, 2-Dibromobutane
(g) 1, 1, 4-Tribromobutane
(f) 2, 2, 3, 3-Tetrabromobutane
(h) 1, 1, 1-TribromobutaneQ:How many signals wouldHow many signals would you expect to find in the 1H NMR spectrum of each of the following compounds?
(a) Vinyl bromide
(d) trans-1, 2-Dibromoethene
(b) 1, 1-Dibromoethene
(e) Allyl bromide
(c) cis-1, 2-Dibromoethene
(f) 2-Methyl-2-buteneQ:Describe the appearance signals would you expect to find,Describe the appearance of the 1H NMR spectrum of each of the following compounds. How many signals would you expect to find, and into how many peaks will each signal be split?
(a) 1, 2-Dichloroethane
(d) 1, 2, 2-Trichloropropane
(b) 1, 1, 1-Trichloroethane
(e) 1, 1, 1, 2-Tetrachloropropane
(c) 1, 1, 2-TrichloroethaneQ:Describe the appearance of the 1H NMR spectrumDescribe the appearance of the 1H NMR spectrum of each of the following compounds. How many signals would you expect to find, and into how many peaks will each signal be split?
(a) ClCH2OCH2CH3
(b) CH3CH2OCH3
(c) CH3CH2OCH2CH3
(d) p-Diethylbenzene
(e) ClCH2CH2OCH2CH3Q:In addition to the proton markedIn addition to the proton marked Ha in m-nitrostyrene in Figure 13.18, there are two other vinylic protons. Assuming that the coupling constant between the two geminal protons in ArCHoeCH2 is 2 Hz and the vicinal coupling constants are 12 Hz (cis) and 16 Hz (Trans) describe the splitting pattern for each of these other two vinylic hydrogens.Q:Describe the splitting pattern expectedDescribe the splitting pattern expected for the proton at
(a) C-2 in (Z)-1, 3-dichloropropene
(b) C-2 in CH3CHCH Showing 400 – 500 of 15569 34567 > >> Join SolutionInn Study Help for 1 Million+ Textbook Solutions Learn the step-by-step answers to your textbook problems, just enter our Solution Library containing more than 1 Million+ textbooks solutions and help guides from over 1300 courses. 24/7 Online Tutors Tune up your concepts by asking our tutors any time around the clock and get prompt responses. Start Membership ×NO, THANKSTRY NOW

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