Organic Chemistry structure and function Textbook Questions And Answers

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Chapter: 17- Aldehydes and Ketones -Problem: 7 >> Indicate which reagent or combination of reagents is best suited for each of the following reactions. (a)(b)(c)(d)(e)(f) Transcribed Image Text: OH
Answer Preview: The given transformation can be done as a MnO 2 is usually used in selective oxidatio…

, Chapter: 14- Delocalized Pi Systems -Problem: 37 >> The structure of the terpene limonene is shown in the margin. Identify the two 2-methyl-1,3-butadiene (isoprene) units in limonene. (a) Treatment of isoprene with catalytic amounts of acid leads to a variety of oligomeric products, one of which is limonene. Devise a detailed mechanism for the acid-catalyzed conversion of two molecules of isoprene into limonene. Take care to use sensible intermedia
Answer Preview: a The two 2 methyl 1 3 butadiene isoprene units in limonene are labeled A and B in the structure Pro…

, Chapter: 25- Heterocycles -Problem: 3 >> Give the expected product of each of the following reaction sequences. (a)(b)(c) Transcribed Image Text: H 1. LIAIH,, (CH,CH,),O 2. H., ?.? H
Answer Preview: a L…

, Chapter: 20- Carboxylic Acid Derivatives -Problem: 23 >> What reagents would be necessary to carry out the following transformations? (a) Cyclohexanecarbonyl chloride ? pentanoylcyclohexane; (b) 2-butenedioic (maleic) anhydride ? (Z)-2-butene1,4-diol; (c) 3-methylbutanoyl bromide ? 3-methylbutanal; (d) benzamide ? 1-phenylmethanamine; (e) propanenitrile ? 3-hexanone; (f) methyl propanoate ? 4-ethyl-4-heptanol.
Answer Preview: a b c d e f C1 Cyclohexane …

, Chapter: 15- Benzene and Aromaticity -Problem: 37 >> Which set of reagents will best carry out the conversion shown? (a) HBr, peroxides; (b) Br2, FeBr3; (c) Br2 in CCl4; (d) KBr Transcribed Image Text: Br
Answer Preview: Answer is option …

, Chapter: 15- Benzene and Aromaticity -Problem: 2 >> Give a proper IUPAC name for each of the following commonly named substances. Transcribed Image Text: CH3 OH OH CH3 LOCH3 (a) (b) (c) H;C HO, ?H3 ?H-(CH,),CH3 CH,CH=CH, Durene Hexylresorcinol Eugenol
Answer Preview: a CH3 b c Structure CH3 OH ochs CH3 CH3 …

, Chapter: 25- Heterocycles -Problem: 26 >> Compound A, C8H8O, exhibits 1H NMR spectrum A. Upon treatment with concentrated aqueous HCl, it is converted almost instantaneously into a compound that exhibits spectrum B. What is compound A, and what is the product of its treatment with aqueous acid? Transcribed Image Text: 'H NMR 5 H 1 H 1 H 7.
Answer Preview: Compound A Molecnlar formula C 8 H 8 0 Degree of unsaturat…

, Chapter: 19- Carboxylic Acids -Problem: 12 >> Propose syntheses of each of the following carboxylic acids that employ at least one reaction that forms a carbon – carbon bond. (a) CH3CH2CH2CH2CH2CH2CO2H(b)(c) Transcribed Image Text: OH CH;CHCH,CO,H
Answer Preview: a b c 0 CH CH CH CH CH CH OH We have a condition that in synthesis we must h…

, Chapter: 18- Enols, Enolates, and the Aldol Condensation -Problem: 5 >> Propose a mechanism for the following reaction. (Take note of all of the products that are formed and base your answer on the mechanism for acid-catalyzed bromination of acetone shown below) Transcribed Image Text: CI Catalytic HCI, CCI + SO,Cl2 + SO, + HCI
Answer Preview: 0 HOCIO …

, Chapter: 14- Delocalized Pi Systems -Problem: 28 >> The haloconduritols are members of a class of compounds called glycosidase inhibitors. These substances possess an array of intriguing biological activity, from antidiabetic and antifungal to activity against HIV virus and cancer metastasis. Stereoisomeric mixtures of bromoconduritol (margin) are commonly used in studies of these properties. One recent synthesis of these compounds proceeds via the
Answer Preview: a In the answer to question a bicyclic ethers means a molecule made up of two rings In this case we …

, Chapter: 24- Carbohydrates -Problem: 3 >> Draw open-chain (Fischer-projection) structures for L-(+)-ribose and L-(-)-glucose (see Exercise 24-2). What are their systematic names? Exercise 24-2Give a systematic name for (a) D-(-)-ribose and (b) D-(+)-glucose. Remember to assign the R and S confi guration at each stereocenter.
Answer Preview: Systematic names 1 L ribose 2S 3S 4S 2 3 4 5 tetrahyd…

, Chapter: 17- Aldehydes and Ketones -Problem: 41 >> The reaction demonstrates (a) Resonance; (b) Tautomerism; (c) Conjugation; (d) De-shielding. Transcribed Image Text: H CH2=C H;C ??
Answer Preview: The reaction demonstrates tautomerism T…

, Chapter: 18- Enols, Enolates, and the Aldol Condensation -Problem: 37 >> When 3-methyl-1,3-diphenyl-2-butanone is treated with excess D2O in the presence of catalytic acid, some of its hydrogens are replaced by deuterium. How many? (a) One; (b) Two; (c) Three; (d) Six; (e) Eight.
Answer Preview: Option b is correct answer The given compound is a ketone When a ketone is treated with excess D2O i…

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, Chapter: 25- Heterocycles -Problem: 5 >> Propose reasonable mechanisms for the following transformations. (a)(b)(c) Transcribed Image Text: 1. SnCl, (a Lewis acid), CH,CI, 2. H', ?.? ?H,OH
Answer Preview: 2 carbocation more stable OH Snch H cHch HHO OH CHOH …

, Chapter: 19- Carboxylic Acids -Problem: 39 >> Interpret the labeled peaks in the mass spectrum of 2-methylhexanoic acid (MS-H). Transcribed Image Text: 74 100 MS CH;CH,CH,CH,CHCOOH 50 CH3 87 45 130 20 40 60 80 100 120 140 160 mlz MS-H Relative abundance
Answer Preview: In MS environment due to high energetic electron beam the compound gets frag…

, Chapter: 18- Enols, Enolates, and the Aldol Condensation -Problem: 33 >> The following steroid synthesis contains modified versions of two key types of reactions presented in this chapter. Identify these reaction types and give detailed mechanisms for each of the transformations shown. Transcribed Image Text: H&C K OCCH.), THF ?O,CH3 H;C H;C K.CO,, CH,OH CO,CH3 CO,CH3
Answer Preview: Michael addition …

, Chapter: 15- Benzene and Aromaticity -Problem: 12 >> Reaction review. Without consulting the Reaction Road Map on p. 721, suggest a reagent to convert benzene into each of the following compounds. Transcribed Image Text: C(CH3)3 NO2 „CH3 CH,CH; SO,H Br (e) (f) (h)
Answer Preview: a b c d …

, Chapter: 24- Carbohydrates -Problem: 11 >> Write the expected products of the reaction of each of the following sugars with (i) Br2, H2O; (ii) HNO3, H2O, 60°C; (iii) NaBH4, CH3OH; and (iv) excess C6H5NHNH2, CH3CH2OH, ?. Find the common names of all the products. (a) D-(-)-Threose; (b) D-(+)-xylose; (c) D-(+)- galactose.
Answer Preview: 1 When glucose reacts with bromine water the main product is gluco…

, Chapter: 17- Aldehydes and Ketones -Problem: 38 >> Three reactions that include compound M (see Problem 62) are described here. Answer the questions that follow. (a) Treatment of M with catalytic amounts of acid in ethanol solvent causes isomerization to compound N: UV ?max(?) = 241(17,500) and 310(72) nm. Propose a structure for N. (b) Hydrogenation of compound N (H2 – Pd, ether solvent) produces compound J (Problem 62). Is this the result that y
Answer Preview: a Treatment of compound M with catalytic amounts of acid in ethanol solvent causes isomerization to …

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, Chapter: 23- Ester Enolates and the Claisen Condensation -Problem: 22 >> Some of the most important building blocks for synthesis are very simple molecules. Although cyclopentanone and cyclohexanone are readily available commercially, an understanding of how they can be made from simpler molecules is instructive. The following are possible retrosynthetic analyses (Section 8-9) for both of these ketones. Using them as a guide, write out a synthesis of each ketone from t
Answer Preview: A B CH3 CH3 CH3 acidic proton Br H30 endisatio…

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, Chapter: 18- Enols, Enolates, and the Aldol Condensation -Problem: 35 >> Write reagents (a, b, c, d, e) where they have been omitted from the following synthetic sequence. Each letter may correspond to one or more reaction steps. This sequence is the beginning of a synthesis of germanicol, a naturally occurring triterpene. The diol used in the step between (a) and (b) provides selective protection of the more reactive carbonyl group.See Problem 63 when formulating (b).
Answer Preview: the short systhsis of germanical a key 2 part of intermediate …

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, Chapter: 24- Carbohydrates -Problem: 1 >> The designations d and l as applied to sugars refer to the configuration of the highest-numbered stereocenter. If the configuration of the highest numbered stereocenter of d-ribose (Figure 24-1) is switched from d to l, is the product l-ribose? If not, what is the product? How is it related to d-ribose (i.e., what kind of isomers are they)?
Answer Preview: The D And L Notation For The Absolute Configuration Of Sugars And Amino Acids The term…

, Chapter: 19- Carboxylic Acids -Problem: 13 >> (a) Write a mechanism for the esterification of propanoic acid with 18O-labeled ethanol. Show clearly the fate of the 18O label. (b) Acid-catalyzed hydrolysis of an unlabeled ester with 18O-labeled water (H2 18O) leads to incorporation of some 18O into both oxygens of the carboxylic acid product. Explain by a mechanism.
Answer Preview: a Esterification of Proponoic acid with CH08 H CH CH 0 H CO H CH CH C CH CH 80 o CH CH …

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, Chapter: 14- Delocalized Pi Systems -Problem: 41 >> The ultraviolet spectrum of a 2×10-4 M solution of 3-penten-2-one exhibits a ???* absorption at 224 nm with A = 1.95 and an n??* band at 314 nm with A = 0.008. Calculate the molar absorptivities (extinction coefficients) for these bands.
Answer Preview: From the formula A log Or Eo E0 1 E0 In first case …

, Chapter: 25- Heterocycles -Problem: 22 >> (a) The compound shown in the margin, with the common name 1,3-dibromo-5,5-dimethylhydantoin, is useful as a source of electrophilic bromine (Br+) for addition reactions. Give a more systematic name for this heterocyclic compound. (b) An even more remarkable heterocyclic compound (ii) is prepared by the following reaction sequence. Using the given information, deduce structures for compounds i and
Answer Preview: a b Systematic na…

, Chapter: 19- Carboxylic Acids -Problem: 32 >> 4- and 5-hydroxy acids can undergo acid-catalyzed intramolecular esterification to produce the corresponding lactone in good yield. Consider the following two examples of lactonization. Divide the analysis of the reaction sequences among your group. Propose reasonable mechanisms to explain the respective product formation. Reconvene to present your mechanisms to each other.
Answer Preview: Br Br Bre oNa Bre JOH H 0 0 OH 0 …

, Chapter: 18- Enols, Enolates, and the Aldol Condensation -Problem: 40 >> The 1H NMR spectrum of 2,4-pentanedione indicates the presence of an enol tautomer of the dione. What is its most likely structure? Transcribed Image Text: H;C, c=c=c_ ?? ?? OH OH OH (?) (b) (?) (d) ?? CH3
Answer Preview: The stracture of the 2 4 pentadione is It tautomer yes to give emulate isomer In 1 we ge…

, Chapter: 14- Delocalized Pi Systems -Problem: 8 >> Rank the following six molecules in approximate order of decreasing SN1 reactivity and decreasing SN2 reactivity. Transcribed Image Text: (?) (b) CI (d) CI (f)
Answer Preview: Reactivity order fo…

, Chapter: 23- Ester Enolates and the Claisen Condensation -Problem: 2 >> Give the expected results of the reaction of each of the following molecules (or combinations of molecules) with excess NaOCH2CH3 in CH3CH2OH, followed by aqueous acidic work-up. (a)(b)(c)(d)(e)(f)(g)(h)(i) Transcribed Image Text: CH;CH,CH,COOCH,CH;
Answer Preview: a The molecule CH3CH2CH2COOCH2CH3 is an ester When it reacts with excess NaOCH2CH3 in CH3CH2OH the ester will undergo a nucleophilic acyl substitution reaction resulting in the formation of a new comp…

, Chapter: 20- Carboxylic Acid Derivatives -Problem: 24 >> Nylon-6,6 was the first completely synthetic fiber, initially prepared in the mid-1930s at DuPont. It is a copolymer whose subunits are alternating molecules of 1,6-hexanediamine and hexanedioic (adipic) acid, linked by amide functions. (a) Write a structural representation of Nylon-6,6. (b) Hexanedinitrile (adiponitrile) may be used as a common precursor to both 1,6-hexanediamine and hexanedioic
Answer Preview: a Structural representation of Nylon 66 b i 1 6 Hexanediamine from Hexanedinitrile ii He…

, Chapter: 16- Electrophilic Attack on Derivatives of Benzene -Problem: 1 >> Rank the compounds in each of the following groups in order of decreasing reactivity toward electrophilic substitution. Explain your rankings. Transcribed Image Text: || OCCH3 CH3 CHCI, CH,CI OCH; O Na+ (?) (b) CH,CH; CH,CCl, CH,CF, CF,CH; (?)
Answer Preview: a Let first compound 1 second compound 2 third compound 3 fourth compound 4 We know that alpha hydro…

, Chapter: 14- Delocalized Pi Systems -Problem: 33 >> Formulate the expected product of each of the following reactions. Transcribed Image Text: H;CO. H,C CH3 hv hv (?) (b) (?) (d) D CH3 H H;C H. CH;Ó
Answer Preview: a b c d OC…

, Chapter: 23- Ester Enolates and the Claisen Condensation -Problem: 31 >> Two of the following four compounds are more acidic than CH3OH (i.e., two of these have Ka greater than methanol). Which ones? (a) A and B; (b) B and C; (c) C and D; (d) D and A; (e) D and B. Transcribed Image Text: CH;CH,OCH,CH3 CH;CCH,CHO CF;CH,OH A B C D
Answer Preview: c So it is more acidic than CH 3 O…

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, Chapter: 26- Amino Acids, Peptides, Proteins, and Nucleic Acids -Problem: 29 >> Factor VIII is one of the proteins participating in the formation of blood clots. A defect in the gene whose DNA sequence codes for Factor VIII is responsible for classic hemophilia. Factor VIII contains 2332 amino acids. How many nucleotides are needed to code for its synthesis?
Answer Preview: There are total 21 amino acid and these 21 amino acids are coded by d…

, Chapter: 16- Electrophilic Attack on Derivatives of Benzene -Problem: 31 >> The intermediate cation A in the sequence C6H6 + E+ ? A ? C6H5E + H+ is best shown as Transcribed Image Text: H H E H E (?) (b) (?) ?? (d) `E
Answer Preview: The mechanism is of electrophile a…

, Chapter: 15- Benzene and Aromaticity -Problem: 9 >> Both methylbenzene (toluene) and 1,6-heptadiyne have molecular formulas of C7H8 and molecular masses of 92. Which of the two mass spectra shown below corresponds to which compound? Explain your reasoning. Transcribed Image Text: 100 MS 100 |MS 50 - 50 – 20 40 60 80 100 20 40 60 80 100 m/z mlz Relat
Answer Preview: The first spectrum is for Toluene The structure elucidation is …

, Chapter: 25- Heterocycles -Problem: 12 >> Propose a synthesis of each of the following substituted heterocycles, using synthetic sequences presented in this chapter. (a)(b)(c)(d) Transcribed Image Text: H3C CH3 H3C CH3
Answer Preview: a It can be easily synthesized by so called Paal Knorr Synthesis in this synthesis we take a 1 4 …

, Chapter: 20- Carboxylic Acid Derivatives -Problem: 8 >> Give the product(s) of the reaction of butanedioic (succinic) anhydride with each of the reagents in Problem 36. Data From Problem 36(a) (CH3)2CHOH (b) NH3 (c)(d) LiAlH4, (CH3CH2)2O; then H+, H2O Transcribed Image Text: MgBr, THF; then H*, H2O
Answer Preview: a b d CH CH H Succinic onhydride The opening of anhydrid…

, Chapter: 18- Enols, Enolates, and the Aldol Condensation -Problem: 14 >> Give the likely products for each of the following aldol addition reactions. Transcribed Image Text: NaOH, H,O (?) 2 -CH,CHO NaOH, H,O (b) -??? + (?H3)??CHO ??? NaOH, H,O CH3 NaOH, H,O (?) ? H3C (d) CH3 ???
Answer Preview: Some important points about Aldol condensation 1 The carbony…

, Chapter: 15- Benzene and Aromaticity -Problem: 21 >> Give efficient syntheses of the following compounds, beginning with benzene. (a) 1-Phenyl-1- heptanol; (b) 2-phenyl-2-butanol; (c) 1-phenyloctane.
Answer Preview: Synthesis of the following compounds beginning wit…

, Chapter: 24- Carbohydrates -Problem: 23 >> Is ?-lactose capable of mutarotation? Write an equation to illustrate your answer.
Answer Preview: Lactose is a distance comprising one glucose molewle linked to a galactose molecule by an B 1 u …

, Chapter: 20- Carboxylic Acid Derivatives -Problem: 5 >> Give the product(s) of each of the following reactions. (a)(b)(c)(d)(e) Transcribed Image Text: NH2 CH;CCI + 2
Answer Preview: a Schotten Baumann reaction This is a method to synthesize amide from amine and acid chlor…

, Chapter: 17- Aldehydes and Ketones -Problem: 15 >> Formulate the mechanism of the BF3-catalyzed reaction of CH3SH with butanal.
Answer Preview: The reaction of Lewis acid cataysed BF3 of methane thiol CH3SH with …

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, Chapter: 23- Ester Enolates and the Claisen Condensation -Problem: 14 >> Using the methods described in this chapter, design a multistep synthesis of each of the following molecules, making use of the indicated building blocks as the sources of all the carbon atoms in your final product. (a)(b)(c) Transcribed Image Text: , from CH;CO,CH,CH; and CH3CCH=CH, CH3
Answer Preview: Answers are given in the figures A C Ans for a Figure A Ans for b Figure …

, Chapter: 20- Carboxylic Acid Derivatives -Problem: 18 >> N,N-Diethyl-3-methylbenzamide (N,N-diethyl-m-toluamide), marketed as DEET, is perhaps the most widely used insect repellent in the world and is especially effective in interrupting the transmission of diseases by mosquitoes and ticks. Propose one or more preparations of DEET (see structure, margin) from the corresponding carboxylic acid and any other appropriate reagents.
Answer Preview: Preparation of DEET From Carboxylic acid 1 Methylation of Ben…

, Chapter: 18- Enols, Enolates, and the Aldol Condensation -Problem: 28 >> Propose syntheses of the following compounds by using Michael additions followed by aldol condensations (i.e., Robinson annulation). Each of the compounds shown has been instrumental in one or more total syntheses of steroidal hormones. Transcribed Image Text: H;C (?) OCH3 (b) ?O,CH,CH; CH, CH3 (?)
Answer Preview: A…

, Chapter: 14- Delocalized Pi Systems -Problem: 16 >> Electrophilic additions to conjugated dienes at low reaction temperatures give kinetic product ratios. Furthermore, these kinetic mixtures may change to mixtures with thermodynamic product ratios when the temperature is raised. Do you think that cooling the thermodynamic product mixture back to the original low reaction temperature will change it back to the original kinetic ratio? Why or why not?
Answer Preview: When njugted diene is ttked by n eletrhile the resulting rduts re mixture f 1 2 nd 1 4 ismers Kinetis nd Thermdynmis ntrl retin when there re tw rduts under different retin nditins The Kineti rdut rdu…

, Chapter: 24- Carbohydrates -Problem: 21 >> (a) Write a detailed mechanism for the isomerization of ?-D-fructofuranose from the hydrolysis of sucrose into an equilibrium mixture of the ?-pyranose and ?-furanose forms. (b) Although fructose usually appears as a furanose when it is part of a polysaccharide, in the pure crystalline form, fructose adopts a ?-pyranose structure. Draw ?-D-fructopyranose in its most stable conformation. In water a
Answer Preview: a The mechanism for the is omer ization of D f ruct of uran ose from the hydro ly sis of suc rose in…

, Chapter: 20- Carboxylic Acid Derivatives -Problem: 9 >> Formulate a mechanism for the reaction of butanedioic (succinic) anhydride with methanol shown on p. 935. Data From Problem 935 Transcribed Image Text: CH,OH ??H; + ?? Alcoholysis (ester formation) 83% Propanoic anhydride Methyl propanoate Propanoic acid
Answer Preview: MECHANISM H 110 0 0 CH…

, Chapter: 18- Enols, Enolates, and the Aldol Condensation -Problem: 25 >> Give the expected product(s) of each of the following reactions. Transcribed Image Text: 1. LDA, THF 2. BICH,COCH, H 1. LDA, THF 2. CH.CH Br, HMPA (a) CH,CCH,CH,CH3 (b) 0:
Answer Preview: LDA is lithium diisopropyl amide strong base which abstracts the …

, Chapter: 25- Heterocycles -Problem: 10 >> Give the expected major product(s) of each of the following reactions. Explain how you chose the position of substitution in each case. (a)(b)(c)(d)(e) Transcribed Image Text: Cl, ???CH}
Answer Preview: a b c…

, Chapter: 19- Carboxylic Acids -Problem: 2 >> Name each of the following compounds according to IUPAC or Chemical Abstracts. Pay attention to the order of precedence of the functional groups. a.b.c.d. Transcribed Image Text: ?? CI
Answer Preview: a 3 Chloro 4 hydroxybutan 2 …

, Chapter: 26- Amino Acids, Peptides, Proteins, and Nucleic Acids -Problem: 34 >> Amino acids can be used as enantiomerically pure starting materials in organic synthesis. Scheme I depicts the first steps in the synthesis of a reagent employed in the preparation of enantiomerically pure ?-amino acids, such as that occurring in the side chain of taxol. Scheme II features an ester of the same amino acid for the preparation of an unusual heterocyclic dipeptide used in the study of
Answer Preview: Scheme I 1 The substitutions on the most stable diastereomer a…

, Chapter: 15- Benzene and Aromaticity -Problem: 35 >> The species that is not aromatic according to Hückel’s rule is Transcribed Image Text: (?) (b) (?) (d)
Answer Preview: For being aromatics the species must be planar it should have conjugation throughout the rings …

, Chapter: 25- Heterocycles -Problem: 25 >> At which position(s) do you expect 3-acetylquinoline (margin) to undergo nitration in the presence of a mixture of sulfuric and fuming nitric acids? Will this reaction be faster or slower than nitration of quinoline itself? Transcribed Image Text: CH3 'N' 3-Acetylquinoline
Answer Preview: Nitration of quinoline Reagents Fuming nitric acid and concentrated sulphuric acid In this …

, Chapter: 20- Carboxylic Acid Derivatives -Problem: 22 >> Formulate a mechanism for the acid-catalyzed hydrolysis of 3-methylpentanamide shown on p. 948. Data From page 948. Transcribed Image Text: Base Hydrolysis of an Amide II.. CH3CH2CH2CNHCH3 II.. > CH3CH2CH2CO:- + CH3NH2 II.. ? CH3CH2CH2COH + CH3NH3 H?:, H,O, A H*, H2O N-Methylbutanamide 87% Butanoi
Answer Preview: Initially the nucleophile attacks the el…

, Chapter: 17- Aldehydes and Ketones -Problem: 9 >> For each of the following groups, rank the molecules in decreasing order of reactivity toward addition of a nucleophile to the most electrophilic sp2 -hybridized carbon. (a)(b)(c) BrCH2COCH3, CH3COCH3, CH3CHO, BrCH2CHO Transcribed Image Text: (CH),?—0, (?H),?—NH, (CH,),?—??
Answer Preview: A CH3COCH3 CH3 2C NH C…

, Chapter: 24- Carbohydrates -Problem: 15 >> (a) Explain why the oxygen at C1 of an aldopyranose can be methylated so much more easily than the other oxygens in the molecule. (b) Explain why the methyl ether unit at C1 of a fully methylated aldopyranose can be hydrolyzed so much more easily than the other methyl ether functions in the molecule.(c) Write the expected product(s) of the following reaction.
Answer Preview: 1 The water molecule is ejected from 1 position in an aldopyranose in a given Scheme after protonati…

, Chapter: 17- Aldehydes and Ketones -Problem: 42 >> Which of the following reagents converts benzenecarbaldehyde (benzaldehyde) into an oxime? (a) H2NNHC6H5; (b) H2NNH2; (c) O3; (d) H2NOH; (e) CH3CH(OH)2.
Answer Preview: Solution Correct option is d NH2OH Explanati…

, Chapter: 26- Amino Acids, Peptides, Proteins, and Nucleic Acids -Problem: 14 >> Using the three-letter abbreviations for amino acids, write the peptide structures in Problem 42 in short notation. Data From Problem 42(a)(b)(c)(d) Transcribed Image Text: CH3 O || HN —CH—C—NH —?H—?-NH—?H- ???" (CH3),CH O HSCH,
Answer Preview: Three letter abbreviations for the following are a Val Ala C…

, Chapter: 17- Aldehydes and Ketones -Problem: 6 >> Reaction review. Without consulting the Reaction Road Map on pp. 816 –817, suggest reagents to convert each of the starting materials below into 3-hexanone. (a)(b)(c)(d)(e)(f)(g)(h) page 816-817 Transcribed Image Text: ??
Answer Preview: a b c d e f g h S …

, Chapter: 23- Ester Enolates and the Claisen Condensation -Problem: 3 >> The following mixed Claisen condensation works best when one of the starting materials is present in large excess. Which of the two starting materials should be present in excess? Why? What side reaction will compete if the reagents are present in comparable amounts? Transcribed Image Text: NaOCH,,
Answer Preview: The two esters involved are Methyl propanoate and 2 Methly propanoate …

, Chapter: 19- Carboxylic Acids -Problem: 31 >> The benzene rings of many compounds in nature are prepared by a biosynthetic pathway similar to that operating in fatty acid synthesis. Acetyl units are coupled, but the ketone functions are not reduced. The result is a polyketide thiolester, which forms rings by intramolecular aldol condensation. o-Orsellinic acid [for structure, see Problem 27(g)] is a derivative of salicylic acid and is prepare
Answer Preview: a o Orsellinic acid is the ester of salicylic acid formed by removal of the two ethyl groups …

, Chapter: 16- Electrophilic Attack on Derivatives of Benzene -Problem: 4 >> Rank the compounds in each of the following groups in order of decreasing reactivity toward electrophilic aromatic substitution. Explain your answers. Transcribed Image Text: CH3 ???? ???? (?) (b) ?H; ???? ?H3
Answer Preview: A Benzene undergoes electrophilic substitution reaction and presence of electron donating groups EDG …

, Chapter: 24- Carbohydrates -Problem: 4 >> Identify the following sugars, which are represented by unconventionally drawn Fischer projections. (It will be necessary to convert these projections into more conventional representations without inverting any of the stereocenters.) (a)(b)(c)(d)(e) Transcribed Image Text: H. ???? ??? OH
Answer Preview: Answer a D Glyceraldehyde Glyceraldehyde glycerol is a triose monosaccharide sugar and has the chemi…

, Chapter: 19- Carboxylic Acids -Problem: 21 >> Show how the Hell-Volhard-Zelinsky reaction might be used in the synthesis of each of the following compounds, beginning in each case with a simple monocarboxylic acid. Write detailed mechanisms for all the reactions in one of your syntheses. (a)(b)(c)(d) HO2CCH2SSCH2CO2H (e) (CH3CH2)2NCH2CO2H (f) Transcribed Image Text:
Answer Preview: Solution Hell Volhard Zelinsky reaction a Mechanism b NH c OH CH OH 1 PBr 1 equ Br …

, Chapter: 16- Electrophilic Attack on Derivatives of Benzene -Problem: 6 >> Write the structure(s) of the major product(s) that you expect from each of the following electrophilic aromatic substitutions. (a) Nitration of methylbenzene (toluene); (b) sulfonation of methylbenzene (toluene); (c) nitration of 1,1-dimethylethylbenzene (tert-butylbenzene); (d) sulfonation of 1,1-dimethylethylbenzene (tert-butylbenzene). In what way does changing the substrate structures from me
Answer Preview: The major product of the given electrophilic aromatic substitution reaction is shown below a nitrati…

, Chapter: 23- Ester Enolates and the Claisen Condensation -Problem: 10 >> Based on your answer to Problem 35, predict whether or not water should catalyze the decarboxylation of each of the following compounds. For each case in which your answer is yes, draw the transition state and the final products. (a)(b)(c)(d) Transcribed Image Text: || (a monoester of carbonic acid)
Answer Preview: It is not possible for me to predict whether or not …

, Chapter: 17- Aldehydes and Ketones -Problem: 26 >> Three isomeric ketones with the molecular formula C7H14O are converted into heptane by Clemmensen reduction. Compound A gives a single product upon Baeyer-Villiger oxidation; compound B gives two different products in very different yields; compound C gives two different products in virtually a 1 : 1 ratio. Identify A, B, and C.
Answer Preview: The degree of unsaturation DU of C 7 H 14 O comes out to be 1 so the ketone s will be ac…

, Chapter: 18- Enols, Enolates, and the Aldol Condensation -Problem: 30 >> Using the following information, propose structures for each of these compounds. (a) C5H10O, NMR spectrum A, UV ?max(e) 5 280(18) nm; (b) C5H8O, NMR spectrum B, UV lmax(e) 5 220(13,200), 310(40) nm; (c) C6H12, NMR spectrum C, UV lmax(e) 5 189(8,000) nm; (d) C6H12O, NMR spectrum D, UV lmax(e) 5 282(25) nm. Next, for each of the following reactions, name an appropriate reagent for the indicated int
Answer Preview: A The structure elucidation is given below The Formula is C5H10O UV max e 5 280 18 nm The formula indicates presence of one Oxygen It indicates that p…

, Chapter: 25- Heterocycles -Problem: 36 >> Identify by name (either IUPAC or common) as many of the heterocyclic rings contained in the structures shown in Table 25-1 as you can. Transcribed Image Text: Top Ten U.S. Prescription Drugs (Ranked by 2007 Sales) by Generic and, in Parentheses, Selected Brand Names Table 25-1 1. Atorvastatin (Lip
Answer Preview: 1 Pyrolle 2 Pyridine and benzimidazole 3 Benzim…

, Chapter: 17- Aldehydes and Ketones -Problem: 34 >> Explain the fact that, although hemiacetal formation between methanol and cyclohexanone is thermodynamically disfavored, addition of methanol to cyclopropanone goes essentially to completion: Transcribed Image Text: HO ?? OCH3 + CH;OH 1
Answer Preview: Hemiacetal formation b w methanol and cyclohexanone is thermodynamically unfavorable This can be …

, Chapter: 17- Aldehydes and Ketones -Problem: 4 >> The compounds described in Problem 27 have very different ultraviolet spectra. One has ?max(?) = 232(13,000) and 308(1450) nm, whereas the other has ?max(?) = 272(35,000) nm and a weaker absorption near 320 nm (this value is hard to determine accurately because of the intensity of the stronger absorption). Match the structures that you determined in Problem 27 to these UV spectral data. Explain th
Answer Preview: The UV spectral data match the structures of a and b as follows a max 232 13 000 and …

, Chapter: 24- Carbohydrates -Problem: 13 >> (a) Which of the aldopentoses (Figure 24-1) would give optically active alditols upon reduction with NaBH4? (b) Using d-fructose, illustrate the results of NaBH4 reduction of a ketose. Is the situation more complicated than reduction of an aldose? Explain. Figure 24-1 Transcribed Image Text: CHO F
Answer Preview: a Since the question is asked for aldopentoses consid…

, Chapter: 20- Carboxylic Acid Derivatives -Problem: 21 >> Give the products of the reactions of pentanamide with the reagents given in Problem 39(a, e, f). Repeat for N,N-dimethylpentanamide. Data From Problem39(a, e, f)(a) NaOH, H2O, heat; then H+, H2O (e) LiAlH4, (CH3CH2)2O; then H+, H2O (f) [(CH3)2CHCH2]2AlH, toluene, low temperature; then H+, H2O
Answer Preview: C 4 H 8 CONH 2 1 NaOH 2 H 3 O C 4 H 8 COOH NH 3 1 LiAlH 4 E…

, Chapter: 18- Enols, Enolates, and the Aldol Condensation -Problem: 27 >> Write the final products of the following reaction sequences. (a)(b)(c)(d) Write a detailed mechanism for reaction sequence (c). Transcribed Image Text: NaOCH, CH,O?, ? O + CH2=CHCCH3
Answer Preview: a b c d HC S CH3 1 LDA THF CH LDA …

, Chapter: 24- Carbohydrates -Problem: 25 >> Identify and, using the information in Sections 24-1 and 24-11, provide names for the carbohydrates that are contained in the structure of stevioside.
Answer Preview: Solution Stevioside is a compound answeed from stevia leaves It is a sweeten…

, Chapter: 19- Carboxylic Acids -Problem: 29 >> Propose two possible mechanisms for the following reaction. (Consider the possible sites of protonation in the molecule and the mechanistic consequences of each.) Devise an isotope-labeling experiment that might distinguish your two mechanisms. Transcribed Image Text: HCI, A CH CH- OH COOH
Answer Preview: According to given reaction CH CH 0 0 010 OH C C OH The given co…

, Chapter: 26- Amino Acids, Peptides, Proteins, and Nucleic Acids -Problem: 3 >> Draw the structure that each of the following amino acids would have in aqueous solution at the indicated pH values. (a) Alanine at pH = 1, 7, and 12;(b) Serine at pH = 1, 7, and 12; (c) Lysine at pH = 1, 7, 9.5, and 12; (d) Histidine at pH = 1, 5, 7, and 12; (e) Cysteine at pH = 1, 7, 9, and 12; (f) Aspartic acid at pH = 1, 3, 7, and 12; (g) Arginine at pH = 1, 7, 12, and 14; (h) Tyrosine at pH =
Answer Preview: a Alumic at PH 1 7 12 b Serine PH 1 7 12 c Lysi…

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, Chapter: 25- Heterocycles -Problem: 7 >> Each of the heterocyclopentadienes in the margin contains more than one heteroatom. For each one, identify the orbitals occupied by all lone electron pairs on the heteroatoms and determine whether the molecule qualifies as aromatic. Are any of these heterocycles a stronger base than pyrrole? Transcribed Image Text:
Answer Preview: Pyrazole imidazole thiazole and isoxazole all are aromatic molecules All the above molecules has 4n …

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, Chapter: 25- Heterocycles -Problem: 33 >> Pyrrole is a much weaker base than azacyclopentane (pyrrolidine) for which of the following reasons?(a) The nitrogen in pyrrole is more electropositive than that in pyrrolidine; (b) Pyrrole is a Lewis acid; (c) Pyrrole has four electrons; (d) Pyrrolidine can give up the proton on the nitrogen atom more readily than can pyrrole; (e) Pyrrole is aromatic.
Answer Preview: So lone availability of pyrrole is very lo…

, Chapter: 18- Enols, Enolates, and the Aldol Condensation -Problem: 18 >> Aldol condensations may be catalyzed by acids. Suggest a role for H1 in the acid-catalyzed version.
Answer Preview: Acid catalysed Aldol condensation In this type of reaction acid can promote further reac…

, Chapter: 23- Ester Enolates and the Claisen Condensation -Problem: 17 >> (a) On the basis of the following data, identify unknowns A, found in fresh cream prior to churning, and B, possessor of the characteristic yellow color and buttery odor of butter. (b) What kind of reaction is the conversion of compound A into compound B? Does it make sense that this should take place in the churning of cream to make butter? Explain. (c) Outline laboratory syntheses of compounds A
Answer Preview: a Unknown A is found in fresh cream prior to churning and unknown B is the possessor of the characte…

, Chapter: 20- Carboxylic Acid Derivatives -Problem: 33 >> Propose a synthetic sequence to convert carboxylic acid A into the naturally occurring sesquiterpene ?-curcumene. Transcribed Image Text: CH3 CH3 CO,H CH3 CH3 H3C CH3 A a-Curcumene
Answer Preview: Me2C PPh3 THF i…

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, Chapter: 25- Heterocycles -Problem: 30 >> The sequence in the margin is a rapid synthesis of one of the heterocycles in this chapter. Draw the structure of the product, which has 1H NMR spectrum F. Transcribed Image Text: 'H NMR 1 H 1 H 3 H 1H. 9.2 8.5 8.4 7.9 7.8 7.7 7.6 7.5 (CH3)4Si 1H 9.5 9.0 8.5 8.0 7.5 7.0 6.5 6.0 5.5 5.0 4.5 4.0 3.5
Answer Preview: The given reaction conditions and nmr data the forming heterocyclic compounds is isoquin…

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, Chapter: 26- Amino Acids, Peptides, Proteins, and Nucleic Acids -Problem: 10 >> (a) Illustrate the Strecker synthesis of phenylalanine. Is the product chiral? Does it exhibit optical activity? (b) It has been found that replacement of NH3 by an optically active amine in the Strecker synthesis of phenylalanine leads to an excess of one enantiomer of the product. Assign the R or S confi guration to each stereocenter in the following structures, and explain why the use of a chir
Answer Preview: Structure synthesis of pharm atomise a Ph CH CH COOH Forward Approach NH …

, Chapter: 24- Carbohydrates -Problem: 10 >> What are the products (and their ratios) of periodic acid cleavage of each of the following substances: (a) 1,3-dihydroxyacetone; (b) rhamnose (Problem 34); (c) glucitol. Problem 34 Transcribed Image Text: ??? H- OH H OH ?? H- (b) ??- -H- CH3 (-)-Rhamnos?
Answer Preview: a b c HO 1…

, Chapter: 19- Carboxylic Acids -Problem: 35 >> The acid whose structure is shown in the margin can best be prepared via one of these sequences. Which one? (a)(b)(c)(d) Transcribed Image Text: HO,C C(CH3)3
Answer Preview: C Ox…

, Chapter: 24- Carbohydrates -Problem: 39 >> The methyl glycoside of mannose is made by treating the sugar with (a) AlBr3, CH3Br; (b) Dilute aqueous CH3OH; (c) CH3OCH3 and LiAlH4; (d) CH3OH, HCl; (e) oxacyclopropane, AlCl3
Answer Preview: ANSW…

, Chapter: 19- Carboxylic Acids -Problem: 16 >> When methyl ketones are treated with a halogen in the presence of base, the three hydrogen atoms on the methyl carbon are replaced to give a CX3-substituted ketone. This product is not stable under the basic conditions and proceeds to react with hydroxide, ultimately furnishing the carboxylic acid (as its conjugate base) and a molecule of HCX3, which has the common name haloform (i.e., chloroform,
Answer Preview: Series of mechanistic steps to convert the tribromoketone into the …

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, Chapter: 23- Ester Enolates and the Claisen Condensation -Problem: 18 >> Write chemical equations to illustrate all primary reaction steps that can occur between a base such as ethoxide ion and a carbonyl compound such as acetaldehyde. Explain why the carbonyl carbon is not deprotonated to any appreciable extent in this system.
Answer Preview: CH 3 CHO C 2 H 5 ONa Na H 2 C CHO C 2 H 5 OH In the above Structure we can see that 3 Hydr…

, Chapter: 19- Carboxylic Acids -Problem: 34 >> Select the acid with the highest Ka (i.e., lowest pKa). (a) H3CCO2H(b)(c)(d) (d) Cl2CHCO2H Transcribed Image Text: CO,H I
Answer Preview: Option D Due …

, Chapter: 23- Ester Enolates and the Claisen Condensation -Problem: 26 >> Split your team in two, each group to analyze one of the following reaction sequences by a mechanism (13C 5 carbon-13 isotope). Reconvene and discuss your results. Specifi cally, address the position of the 13C label in the product of (a) and the failure to obtain alkylation in (b). As a complete team, also discuss the mechanism of the following transformation.
Answer Preview: The reaction sequence involves the conversion of CH3CH2CH2CH2Li 2 into CH3CH2CH2CH2OH 4 The steps in…

, Chapter: 19- Carboxylic Acids -Problem: 8 >> When 1,4- and 1,5-dicarboxylic acids, such as butanedioic (succinic) acid (Section 19-8), are treated with SOCl2 or PBr3 in attempted preparations of the diacyl halides, the corresponding cyclic anhydrides are obtained. Explain mechanistically.
Answer Preview: OH 1 4 butane diric acid HO OH 0 soci HO 1 5 pentane dioic acid …

, Chapter: 23- Ester Enolates and the Claisen Condensation -Problem: 7 >> Devise a synthesis for each of the following four compounds by using the malonic ester synthesis. (a)(b)(c)(d) Transcribed Image Text: HO
Answer Preview: a b c d u EtO OEt …

, Chapter: 14- Delocalized Pi Systems -Problem: 5 >> Give the major product(s) of each of the following reactions. (a)(b)(c)(d)(e)(f) Transcribed Image Text: OH Conc. HBr
Answer Preview: These reactions are nucleophilic substitution reactions A s…

, Chapter: 12- Reactions of Alkenes -Problem: 36 >> When a cis alkene is mixed with a small amount of I2 in the presence of heat or light, it isomerizes to some trans alkene. Propose a detailed mechanism to account for this observation.
Answer Preview: Mechanism Step …

, Chapter: 14- Delocalized Pi Systems -Problem: 10 >> Give the major product(s) of each of the following reactions. (a)(b)(c)(d)(e)(f) Transcribed Image Text: H;C I HO H
Answer Preview: a H3C b Solut…

, Chapter: 25- Heterocycles -Problem: 20 >> Derivatives of benzimidazole possess biological activity somewhat like that of indoles and purines. Benzimidazoles are commonly prepared from benzene-1,2-diamine. Devise a short synthesis of 2-methylbenzimidazole from benzene-1,2-diamine. Transcribed Image Text: NH2 N -CH3 N' NH2 H Benzene-1,2-diam
Answer Preview: 2 methyl benzimidazole can be synthesized by reactio…

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, Chapter: 13- Alkynes -Problem: 13 >> Write the mechanism and final product for the reaction of 1-propynyllithium with trans-2,3- dimethyloxacyclopropane.
Answer Preview: Trans 2 3 dimethyloxacyclopropane is an epoxide In the present reaction 1 pro…

, Chapter: 25- Heterocycles -Problem: 32 >> The proton decoupled 13C NMR spectrum of pyridine will display how many peaks? (a) One; (b) Two; (c) Three;(d) Four; (e) Five.
Answer Preview: Proton decoupled 13C spectra is the spectra which does not show the spin spin splitt…

, Chapter: 14- Delocalized Pi Systems -Problem: 13 >> Starting with cyclohexene, propose a reasonable synthesis of the cyclohexene derivative shown in the margin. Transcribed Image Text: OH
Answer Preview: First we do bromination of cyclohexene hence we get 3 bromo cyclohex…

, Chapter: 24- Carbohydrates -Problem: 38 >> Vitamin C is present almost universally in the plant and animal kingdoms. (According to Linus Pauling, mountain goats biosynthesize from 12 to 14 g of it per day.) Animals produce it from D-glucose in the liver by the four-step sequence D-glucose ? D-glucuronic acid (see Problem 62) ? D-glucuronic acid ?-lactone n l-gulonic acid ?-lactone ? vitamin C. The enzyme that catalyzes the last reaction,
Answer Preview: The task is to write the missing reagents and draw the missing structures Task a is to write the rea…

, Chapter: 17- Aldehydes and Ketones -Problem: 40 >> In the transformation shown here, which of the following compounds is most likely to be compound A (use IUPAC name)? (a) 5-Octyn-7-one; (b) 5-octyn-2-one; (c) 3-octyn-2-one; (d) 2-octyn-3-one. Transcribed Image Text: 3-Octyn-2-ol CrO,, H,SO, acetone A
Answer Preview: ANSWER 3 octyn 2 one CrO3 H2SO4 ACETONE This is known as JONES Reagent Jones Reagent is USE for t…

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, Chapter: 26- Amino Acids, Peptides, Proteins, and Nucleic Acids -Problem: 8 >> What amino acid would result from carrying out the following synthetic sequence on 1. CH3CH2O2Na+ , CH3CH2OH; 2. Br(CH2)4NHCOCH3; 3. H+, H2O, ?. Transcribed Image Text: N-CH(CO,CH,CH3),?
Answer Preview: Finally we will get Lysine basic amino acid all steps are mentio…

, Chapter: 13- Alkynes -Problem: 25 >> Propose a reasonable structure for calcium carbide, CaC2, on the basis of its chemical reactivity (Section 13-10). What might be a more systematic name for it?Section 13-10Ethyne chemistry underwent important commercial development in the 1930s and 1940s in the laboratories of Badische Anilin and Sodafabriken (BASF) in Ludwigshafen, Germany. Ethyne under pressure was brought into reaction with car
Answer Preview: One calcium atom and two carbon atoms make up the chemical known as calcium carbide CaC2 Due to the …

, Chapter: 25- Heterocycles -Problem: 15 >> Chelidonic acid, a 4-oxacyclohexanone (common name, g-pyrone), is found in a number of plants and is synthesized from acetone and diethyl ethanedioate. Formulate a mechanism for this transformation. Transcribed Image Text: 00 1. NaOCH,CH, C? CH,?H 2. ??I, ? CH;CCH; + 2CH;CH,OCCOCH,CH3 ????" ???? Ch
Answer Preview: Mechanism CH3 …

, Chapter: 19- Carboxylic Acids -Problem: 27 >> SN2 reactions of simple carboxylate ions with haloalkanes in aqueous solution generally do not give good yields of esters. (a) Explain why this is so. (b) Reaction of 1-iodobutane with sodium acetate gives an excellent yield of ester if carried out in acetic acid (as shown here). Why is acetic acid a better solvent for this process than water? (c) The reaction of 1-iodobutane with sodium dodecano
Answer Preview: a SN2 reactions of simple carboxylate ions with haloalkanes in aqueous solution generally doesn t gi…

, Chapter: 12- Reactions of Alkenes -Problem: 45 >> A chiral compound, C5H8, upon simple catalytic hydrogenation, yields an achiral compound, C5H10. What is the best name for the former?(a) 1-Methylcyclobutene;(b) 3-methylcyclobutene;(c) 1,2-dimethylcyclopropene;(d) cyclopentene.
Answer Preview: The structures of 1 Methylcyclobutene 1 2 dimethylcyclopropene and cyclopente…

, Chapter: 24- Carbohydrates -Problem: 34 >> What kind of sugar is the compound shown in the margin? (a) An aldopentose; (b) A ketopentose; (c) An aldohexose; (d) A ketohexose Transcribed Image Text: ??? H- OH CH,OH OH ????-??CHCH-CH ??
Answer Preview: The correct option is a Aldopentose Explanation This sug…

, Chapter: 17- Aldehydes and Ketones -Problem: 37 >> In 1862, it was discovered that cholesterol is converted into a new substance named coprostanol by the action of bacteria in the human digestive tract. Make use of the following information to deduce the structure of coprostanol. Identify the structures of unknowns J through M as well. (i) Coprostanol, upon treatment with Cr(VI) reagents, gives compound J, UV ?max(?) = 281(22) nm and IR = 1710 cm-
Answer Preview: The structure of coprostanol is C27H44O Compound J is C27H44O2 compound K is C27H44O2 comp…

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, Chapter: 25- Heterocycles -Problem: 4 >> The penicillins are a class of antibiotics containing two heterocyclic rings that interfere with the construction of cell walls by bacteria (Chemical Highlight 20-2). The interference results from reaction of the penicillin with an amino group of a protein that closes gaps that develop during construction of the cell wall. The insides of the cell leak out, and the organism dies. (a) Suggest a reas
Answer Preview: a The formation of this derivative blocks the synthe…

, Chapter: 17- Aldehydes and Ketones -Problem: 21 >> Reaction review II. Without consulting the Reaction Road Map on p. 818, suggest reagents to convert cyclohexanone into each of the compounds below. Transcribed Image Text: -5 -8 - OH ?? CH2CH3 ?? CN (b) (?) (d) N(CH,CH,), (?) (f) (h) CH;O OCH; ?? (i) (j) (k) (1)
Answer Preview: a b c d O Reagent NaBH4 THF OH Reduction of kotone to aldohol using NaBH4 S SH 608 SH …

, Chapter: 10- Using NMR Spectroscopy to Deduce Structure -Problem: 23 >> 1H NMR spectra C through F (see below) correspond to four isomeric alcohols with the mole cular formula C5H12O. Try to assign their structures. Transcribed Image Text: 1? ?MR 6 H 3 H 'H NMR 6 H 1 H 2 H 1.5 1.4 1.3 0.9 0.8 0.7 1.8 1.7 1.6 1.5 1.4 2 H (CH3)4Si (CH3)4Si 2H 1 H 1 H 3.0 2.5 2.0 1.5 1.0
Answer Preview: C In the spectra there is a peak which integrates 6 hydrogen which is singlet This means there is tw…

, Chapter: 24- Carbohydrates -Problem: 2 >> To which classes of sugars do the following monosaccharides belong? Which are d and which are L? Transcribed Image Text: CH,OH ??? H- OH ?? H. ??? H- OH ??- H- H- -OH HO H OH (?) ???? OH (b) ??— H- OH- CH,OH CH3 CH,OH (+)-?piose (-)-Rhamnose (+)-Mannoheptulose
Answer Preview: To find out D or L we have to look at the lowest most …

, Chapter: 19- Carboxylic Acids -Problem: 26 >> Suggest structures for the products of each reaction in the following synthetic sequence. Transcribed Image Text: 1. H, H* 2. (CH,),C=CHCH,Br 3. H*, H,O 1. O. CH;CI; 2. Zn, CH,COOH 3. KMNO,, NaHCO, H HOCH,CH,OH, H ? C16H2602 H I H IR: 1745 cm IR: 1675 and 1745 cm IR: 1670 cm 1. H*, H,O 2. NaBH, Cat
Answer Preview: Reacting the starting material with cyclopentylamine in acidic environment will generate an enamine …

, Chapter: 13- Alkynes -Problem: 8 >> Deduce structures for each of the following.(a) Molecular formula C6H10; NMR spectrum A; no strong IR bands between 2100 and 2300 or 3250 and 3350 cm-1.(b) Molecular formula C7H12; NMR spectrum B; IR bands at about 2120 and 3330 cm-1.(c) The percentage composition is 71.41% carbon and 9.59% hydrogen (the remainder is O), and the exact molecular mass is 84.0584; NMR and IR spectra C (next page). Th
Answer Preview: a cyclohexene i e a 6 membered ring with 1 double bond decree of unsaturation 2x6 …

, Chapter: 26- Amino Acids, Peptides, Proteins, and Nucleic Acids -Problem: 25 >> Secreted by the pituitary gland, corticotropin is a hormone that stimulates the adrenal cortex. Determine its primary structure from the following information. (i) Hydrolysis by chymotrypsin produces six peptides: Arg-Trp, Ser-Tyr, Pro-Leu-Glu-Phe, Ser-Met-Glu-His-Phe, Pro-Asp-AlaGly-Glu-Asp-Gln-Ser-Ala-Glu-Ala-Phe, and Gly-Lys-Pro-Val-Gly-Lys-Lys-Arg-Arg-Pro-ValLys-Val-Tyr. (ii) Hydrolysis by try
Answer Preview: the hormone is adrenocorticotropic hormones acth consist of 39 amino acid long peptide whose sequenc…

, Chapter: 18- Enols, Enolates, and the Aldol Condensation -Problem: 38 >> How would you best classify the following reaction? (a) Wittig reaction; (b) Cyanohydrin formation; (c) Conjugate addition; (d) Aldol addition. Transcribed Image Text: H. NC -> H2C=CHCH=N H. NCCH;CH=CHNH,
Answer Preview: The correct option is C Conjugate addition These are basically …

, Chapter: 24- Carbohydrates -Problem: 29 >> Write or draw the missing reagents and structures (a) through (g). What is the common name of (g)? The preceding sequence (called the Weerman degradation) achieves the same end as what procedure described in this chapter? Transcribed Image Text: NH,, A Brz, NaOH D-(+)-Xylose (b) (d) C3H1|NOs -> D-X
Answer Preview: H OH H OH CHOH D XYLOSE Br2 NaOH CO2 XYLOSE …

, Chapter: 19- Carboxylic Acids -Problem: 4 >> Rank each of the following groups of organic compounds in order of decreasing acidity.(a)(b)(c)(d)(e) Transcribed Image Text: CH;CH,CO,H, CH;CCH,OH, CH;CH,CH,OH
Answer Preview: a Pka of Propanol 16 Therefore the order decreasing acidity CH 3 CH 2 COOH CH 3 C CH 2 OH CH 3 CH 2 CH 2 OH b BrCH 2 COOH Cl CH 2 COOH FCH 2 COOH We k…

, Chapter: 13- Alkynes -Problem: 18 >> Give the expected major product of the reaction of propyne with each of the following reagents.(a) D2, Pd – CaCO3, Pb(O2CCH3)2, quinoline;(b) Na, ND3;(c) 1 equivalent HI;(d) 2 equivalents HI;(e) 1 equivalent Br2;(f) 1 equivalent ICl;(g) 2 equivalents ICl;(h) H2O, HgSO4, H2SO4;(i) dicyclohexylborane, then NaOH, H2O2.
Answer Preview: Propyne CH 3 C CH a CH3 C CH b CH3 C CH c CHg C CH d CH3 C CH e CH3 C CH f CH C …

, Chapter: 18- Enols, Enolates, and the Aldol Condensation -Problem: 36 >> When 2-methylcyclopentanone is treated with the bulky base triphenylmethyllithium under the two sets of conditions shown, the two possible enolates are generated in differing ratios. Why is this so? To tackle this problem, you have to invoke the principles of kinetic versus thermodynamic control; that is, which enolate is formed faster and which one is more stable? Divide your team so that one gro
Answer Preview: Ha CH3 C6H CL Hb C Ph 3L CH3 O L L Condition A is kinetic…

, Chapter: 24- Carbohydrates -Problem: 24 >> Trehalose, sophorose, and turanose are disaccharides. Trehalose is found in the cocoons of some insects, sophorose turns up in a few bean varieties, and turanose is an ingredient in low-grade honey made by bees with indigestion from a diet of pine tree sap. Identify among the following structures those that correspond to trehalose, sophorose, and turanose on the basis of the following information:
Answer Preview: From the given information Turanose and Sophorose are reducig sugars whereas Trehalose is a no red…

, Chapter: 11- Solving Problems in Organic Chemistry -Problem: 28 >> You have just entered the chemistry stockroom to look for several isomeric bromopentanes. There are three bottles on the shelf marked C5H11Br, but their labels have fallen off. The NMR machine is broken, so you devise the following experiment in an attempt to determine which isomer is in which bottle: You first treat a sample of the contents in each bottle with NaOH in aqueous ethanol, and then yo
Answer Preview: a According to given data following conclusions can …

, Chapter: 16- Electrophilic Attack on Derivatives of Benzene -Problem: 29 >> Polystyrene (polyethenylbenzene) is a familiar polymer used in the manufacture of foam cups and packing beads. One could, in principle, synthesize polystyrene by cationic polymerization with acid. However, this approach is unsuccessful because of the formation of dimer A. Split your group into two teams. The first should formulate a mechanism for the cationic polymerization of styrene using acid;
Answer Preview: Polystyrene polyethenylbenzene is a familiar polymer used in the manufacture …

, Chapter: 23- Ester Enolates and the Claisen Condensation -Problem: 25 >> Propose a synthesis of ketone C, which was central in attempts to synthesize several antitumor agents. Start with aldehyde A, lactone B, and anything else you need. Transcribed Image Text: ??? H,C H2C A B C
Answer Preview: Kmno41 SOCI H …

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, Chapter: 26- Amino Acids, Peptides, Proteins, and Nucleic Acids -Problem: 21 >> Write the