Write a structural formula or build a molecular model and give a correct IUPAC name for each alkene of molecular formula C7H14 that has a tetrasubstituted double bond.
Choose the compound of molecular formula C7H13Br that gives each alkene shown as the exclusive product of E2 elimination.
There are two other stereoisomeric tartaric acids. Write their Fischer projections, and specify the configuration at their stereogenic centers.
(a) An aqueous solution containing 10 g of optically pure fructose was diluted to 500 mL with water and placed in a polarimeter tube 20 cm long. The measured rotation was _5.20. Calculate the...
Write the structure of the major organic product isolated from the reaction of 1-hexyne with (a) Hydrogen (2 mol), platinum (b) Hydrogen (1 mol), Lindlar palladium (c) Lithium in liquid ammonia (d)...
Both 1, 2-dihydronaphthalene and 1, 4-dihydronaphthalene may be selectively hydrogenated to 1, 2, 3, 4-tetrahydronaphthalene.
Give 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,...
Evaluate each of the following processes applied to cyclononatetraene, and decide whether the species formed is aromatic or not: (a) Addition of one more electron, to give C9H10 (b) Addition of two...
Write structural formulas for the cyclohexadienyl cations formed from aniline (C6H5NH2) during (a) Ortho bromination (four resonance structures) (b) Meta bromination (three resonance structures) (c)...
In 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...
Using benzene and any necessary organic or inorganic reagents, suggest efficient syntheses of (a) Isobutyl benzene, C6H5CH2CH (CH3)2 (b) Neopentylbenzene, C6H5CH2C (CH3)3
How 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,...
Which of the isomeric C4H10O alcohols can be prepared by hydrogenation of aldehydes? Which can be prepared by hydrogenation of ketones? Which cannot be prepared by hydrogenation of a carbonyl...
Outline practical syntheses of each of the following compounds from alcohols containing no more than four carbon atoms and any necessary organic or inorganic reagents. In many cases the desired...
The fungus responsible for Dutch elm disease is spread by European bark beetles when they burrow into the tree. Other beetles congregate at the site, attracted by the scent of a mixture of chemicals,...
Nitro-substituted aromatic compounds that do not bear halide leaving groups react with nucleophiles according to the equation
The imidazole ring of the histidine side chain acts as a proton acceptor in certain enzymecatalyzed reactions. Which is the more stable protonated form of the histidine residue, A or B? Why?
How many peaks would you expect to see on the strip chart after amino acid analysis of bradykinin? Arg-Pro-Pro-Gly-Phe-Ser-Pro-Phe-Arg Bradykinin
Show by writing the appropriate sequence of equations how you could carry out each of the following transformations: (a) 1-Butanol to 1-pentanamine (b) tert-Butyl chloride to 2,...
(a) Show the unshared electron pairs on the following anion, The S has a formal charge of ? 1, and the formal charges of the other atoms are zero. (b) Draw a resonance structure for this ion, -...
Amino acids, from which proteins are formed, exist as ?dipolar ions.? The structure of the dipolar ion of the amino acid alanine is (a) Calculate the formal charges on all of the atoms, except...
Ammonium cyanate is composed of an ammonium caution (NH 4 + ) and a cyanate anion (OCN ). Show a Lewis structure for the cyanate anion. (Both O and N are bonded to C.) Which atom has the negative...
(a) Show a Lewis structure for urea. CH 4 N 2 O. Both Ns and the O are bonded to the C. The Hs are bonded to the Ns. None of the atoms has a formal charge. (b) Show a Lewis structure of an isomer of...
Although carbon?carbon double bonds are shorter than carbon?carbon single bonds, all of the carbon?carbon bonds of benzene are the same length. Explain. H. H C. H H Benzene H H
Amino acids such as alanine actually exist as species called zwitterions, with a positive charge on the nitrogen and a negative charge on the oxygen. Explain what effect you expect this to have on...
Arrange these compounds in order of increasing acid strength: CHOH CN CN
Arrange these compounds in order of increasing base strength: NH NH NH NO 9 CH,CNH,
Arrange these compounds in order of increasing acid strength: CH3COH .. HOC-COH HOCCH2CH2COH
Amino acids contain both a basic functional group, the amine, and an acidic functional group, the carboxylic acid. Thus, they can undergo an internal acid-base re-action as shown in the following...
Assign these compounds as the Z or Eisomers: a) HC C-C CHCH2 CHCI CH3 N OH b) H F C=C C=CH CHCH
Assign the configurations of these compounds as Z or E: 3 CH,CH2CH3 C=C CH,Br C=C HOCH,CH2 b) a) H,NCH, CH,CHCH3 CH,CH CH3 H3 - HO- Ph c) d)
Assign the configurations of the compounds represented by these Fischer projections as R or S. CH -CH2CH3 b) CH2=CH- ) >N- CH-OH CH3 Serine
Assign priorities to the groups attached to the chirality centers of these molecules and determine whether they have the R or S configuration: . CI .. b) Br a) CCH3 CH3CH CI CH3O CH3, d) c) Ph CI...
Although this biphenyl is chiral, it cannot be resolved. Explain. HO-C CH30 CO H OCH
Assign the configuration of these compounds as R or S: a) c) e) CH3 HC C HOCH H HC g) H- B CH CH3 i) HN- -OH CH H CH3 COH FH H CH,Ph Phenylalanine b) d) f) Br CH3 "CO,H h) H- me H to Br OH -CH3...
All naturally occurring amino acids have the same relative configuration. All have the S absolute configuration, except for cysteine, which has the R configuration.Explain. CO.H H,N-C-H CH,SH Cysteine
Indicate whether these compounds are identical, enantiomers, or diastereomers.
Arrange these compounds in order of decreasing SN2 reaction rate: CHCL CI Cl
Arrange these compounds in order of decreasing SN1 reaction rate. Ph CI CI CI Ph CI Ph
(a) Show all the steps in the mechanism for this reaction. Don't forget to use curved arrows to show the movement of electrons in each step of the mechanism. (b) Show a free energy versus reaction...
Amino acids can be prepared (as their conjugate bases) by the reaction of a bromine substituted carboxylic acid with excess ammonia. (a) The conjugate base of the amino acid alanine is formed in the...
Arrange these nucleophiles in order of decreasing rate of reaction with iodomethane and explain your answer. Problems using online three-dimensional molecular models
All of the stereo isomers of 1, 2, 3, 4, 5, 6-hexachlorocyclohexane have very similar rates of E2 reaction except the following stereo isomer, which reacts about 7000 times more slowly than the...
Arrange these alkenes in order of increasing rate of reactio0n with HCI: CH, CH2=CH2 a) CH;CH2CH=CH2 CH;CH,C=CH, -CH=CH; CH=CH2 CH,CH-CH b) CHO
An unknown compound has the formula C6H10. (a) What is the DU for this compound? (b) When a solution of Br2 in CC14 is added to the unknown, the bromine color disappears. What information does this...
Calculate these quantities: (a) The wavelength of light (in centimeters) with a frequency of 9.00 x 1012Hz. (b) The frequency of light with a wavelength of 310nm (c) The energy of light (in kcal/mol...
Assign the absorptions in the 13C-NMR spectra of these compounds to the appropriate carbons: (a) 1-Butanol; absorptions at 61.4, 35.0, 19.1, and 13.6 (b) Cyclohexanone; absorptions at 209.7, 41.9,...
Anthracene has 1.80 x 105 M1 cm1 at max = 256nm calculate the absorbance of a 1.94 x 106M solution of anthracene in a 1 cm cell.
An unknown compound has the formula C7H12. (a) What is the DU for this compound? (b) The unknown reacts with H2 in the presence of Pd to give C7H16. What information dos these provide about the...
A solution of a 0.0014 g of benzophenone in 1 L of ethanol has A = 0.153 (1 cm cell) at ? max = 252 nm. Calculate the molar absorptivity of benzophenone. Benzophenone
(a) The base ion in the mass spectrum of 3-ethyl-2-methylpentane occurs at m/z 43m; show the fragmentation that produces this ion. (b) What other fragment would you predict to provide a major peak in...
Allene, H2C = C = CH2, is somewhat unusual in that it has two adjacent double bonds. Draw a picture showing the orbitals involved in the and bonds of allene. Is the central atom sp2- or...
Allene (see problem 1.46) is related structurally to carbon dioxide, CO2. Draw a picture showing the orbitals involved in the and bonds CO2, and identify the likely hybridization of carbon.
Almost all stable organic species have tetravalent carbon atoms, but species with trivalent carbon atoms also exist. Carbocations are one such class of compounds. (a) How many valence electrons do...
Amide ion, H 2 N , is a stronger base then hydroxide ion, HO . Which is the stronger acid, NH 3 or H 2 O? Explain.
Ammonia, NH3, has pKa = 36 and acetone has pKa 19. Will the following reaction takeplace? Na* -:NH2 NH3 CH H Acetone Na+ CH2:
Among the most common over-the-counter drugs you might find in a medicine cabinet are mild pain relievers such ibuprofen (Advil, Motrin), naproxen (Aleve), and acetaminophen (Tylenol). (a) How many...
(a) The H C1 bond length is 136 pm. What would the dipole moment of HC1 be if the molecule were 100% ionic, H+ C1-? (b) The actual; dipole moment HC1 is 1.08 D. What is the percent ionic character...
Alcohols can act either as weak acid or as weak bases, just as water can. Show the reaction of methanol, CH 3 OH, with a strong acid as HC1 and with a strong base such as NA + - NH 2 .
Assign formal charger to the atoms in each of the followingmolecules: ( NNEN: CH (c) HCN3DN-DN: (a) H3C-N-O: CH
Assume that you have two unlabeled bottles, one of the following which contains phenol (pKa = 9.9) and one of which contains acetic acid (pKa = 4.76). In light of your answer to Problem 2.51, suggest...
An electrostatic potential map of (trifluoromethyl) benzene, C6H5CF3, is shown. Would you expect (trifluoromethyl) benzene to be more reactive or less reactive than toluene toward electrophilic...
Acetanilide is less reactive than aniline toward electrophilic substitution.Explain. c%3D0 Acetanilide CH
Aromatic iodination can be carried out with a number of reagents, including iodine mono chloride, ICI. What is the direction of polarization of ICI? Propose a mechanism for the iodination of an...
Addition of HBr to 1-phenyipropene yields only (1-bromopropyl) benzene. Propose a mechanism for the reaction, and explain why none of the other regioisomer isproduced. Br + HBr
Acid-catalyzed hydrolysis of a 1, 2-epoxycyclohexane produces a trans-diaxial 1, 2diol. What product would you expect to obtain from acidic hydrolysis of cis-3-tert-butyl-1, 2-epoxycyclohexane?...
Anethole, C10H12O, a major constituent of the oil of anise, has the 1H NMR spectrum shown. On oxidation with Na2Cr2O7, Anethole yields p-methoxybenzoic acid. What is the structure of Anethole? Assign...
Aldehydes and ketones undergo acid-catalyzed reaction with alcohols to yield hemiacetals, compounds that have one alcohol-like oxygen and one ether-like oxygen bonded to the same carbon. Further...
Assume that you need to prepare 5-cholesten-3-one from cholesterol. How could you use IR spectroscopy to tell whether the reaction was successful? What differences would you look for in the IR...
As a rule, axial alcohols oxidize somewhat faster than equatorial alcohols. Which would you expect to oxidize faster, cis-4-tert-butylcyclohexanol or trans-4-tert-butylcyclohexanol? Draw the more...
A problem often encountered in the oxidation of primary alcohols to acids is that esters are sometimes produced as by-products. For example, oxidation of ethanol yields acetic acid and ethyl acetate:...
A trisubstituted cyclohexane with three substituents? red, yellow, and blue?undergoes a ring-flip to its alternative chair conformation. Identify each substituent as axial or equatorial, and show the...
A1, 2-cis disubstituted cyclohexane, such as cis-1, 2-dichlorocyclohexane, must have one group axial and one group equatorial. Explain.
Approximately how much steric strain does the 1, 3-diaxial interaction between the two methyl groups introduce into the diaxial conformation of cis-1, 3-dirnethylcyclohexanc?
Amantadine is an antiviral agent that is active against influenza A infection and against some strains of H5N1 avian flu. Draw a three-dimensional representation of amantadine showing the chair...
Alcohols undergo an oxidation reaction to yield carbonyl compounds on treatment with CrO 3 . For example, 2-tert-butylcyclohexanol gives 2-tert-butylcyclo- hexanone. If axial ?OH groups are generally...
An electrostatic potential map of boron trifluoride is shown. Is BF3 likely to be a nucleophile or an electrophile? Draw a Lewis structure for BF3, and explain youranswer. BF3
Add curved arrows to the following polar reactions to indicate the flow of electrons in each: :Ci: (a) - :- + -N :CI: -NH (b) H CH: -Br: :Br: (c) :0: :CI: CI "
An Add curved arrows to the following reactions to indicate the flow of electrons ineach: (a) H-CI D-CI = H. H. (b) -I CH CH CH
Add curved arrows to the mechanism shown in Problem 5.32 to indicate the electron movement in each step.
An Add curved arrows to the mechanism shown in Problem 5.34 to indicate the electron movement in each step.
?-Carotene a yellow food-coloring agent and dietary source of vitamin A, can be prepared by a double Witting reaction between 2 equivalents of ?-ionylideneacetaldehyde and a diylide. Show the...
Assign R or S stereochemistry to the two chirality centers in isocitrate, and tell whether OH and H add to the Si face or the Re face of the double bond.
Aldehydes can be prepared by the Wittig reaction using (methoxymethylene)-triphenylphosphorane as the Wittig reagent and then hydrolyzing the product with acid. For example, (a) How would you prepare...
Aldehydes and ketones react with thiols to yield thioacetals just as they react with alcohols to yield acetals. Predict the product of the following reaction, and propose a mechanism: H* catalyst 2...
Assume you have a mixture of naphthalene and benzoic acid that you want to separate. How might you take advantage of the acidity of one component in the mixture to effect a separation?
Arrange the compounds in each of the following sets in order of increasing basicity: (a) Magnesium acetate, magnesium hydroxide, methyl magnesium bromide (b) Sodium benzoate, sodium p-nitro benzoate,...
Acid-catalyzed hydrolysis of a nitrile to give a carboxylic acid occurs by initial Protonation of the nitrogen atom, followed by nucleophilic addition of water. Review the mechanism of base-catalyzed...
Assign F or Z configuration to the following alkenes: (a) CH2 (b) CCH C=C C=C CH3CH2 CI CH2CH2CH3 CH30 (e) CH (d) CN O C=C C=C CH2NH2 C-
Assign stereochemistry (E or Z) to the double bond in the following compound, and convert the drawing into a skeletal structure (red0):
? - Farnesene is a constituent of the natural wax found on apples. What is its IUPAC name, including stereo chemistry? a-Farnesene
Allene (1, 2-propadiene), H2C = C = CH2, has two adjacent double bonds. What kind of hybridization must the central carbon have? Sketch the bonding orbitals in allene. What shape do you predict for...
An Assign E or Z configuration to each of the following alkenes: ( - C (a) H2 C=C C=C H3C ci OCH3 (c) (d) CH3O2C CH=CH2 NC CH C=C CH3CH2 CH2 HO2C CH-CH
A tert-l3utyI esters [RCO2C (CH3)3] are converted into carboxylic acids (RCO2H) by reaction with trifluoroacetic acid, a reaction useful in protein synthesis (Section 26.7). Assign E, Z designation...
Addition of HCI to 1-isopropylcyclohexene yields a rearranged product. Propose a mechanism, showing the structures of the intermediates and using curved arrows to indicate electron flow in each step....
Addition of HCI to 1-isopropcnyl-1-methylcyclopcntane yields 1-chloro-1, 2, 2- trimethylcyclohexane. Propose a mechanism, showing the structures of the intermediates and using curved arrows to...
Aromatic compounds such as benzene react with alkyl chlorides in the presence of A1C1 3 catalyst to yield alkylbenzenes. The reaction occurs through a carbocation intermediate, formed by reaction of...
Alkenes can be converted into alcohols by acid-catalyzed addition of water. Assuming that Markovnikov?s rule is valid, predict the major alcohol product from each of the following alkenes. H CH3CH-CH...
Addition of HC1 to 1, 2-dimethylcyclohexene yields a mixture of two products. Show the stereochemistry of each, and explain why a mixture is formed.
An unknown hydrocarbon A with the formula C6H12 reacts with 1 molar equivalent of H2 over a palladium catalyst. Hydrocarbon A also reacts with OsO4 to give diol B. When oxidized with KMnO4 in acidic...