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1 Million+ Step-by-step solutionsmath books Q:Identify all the acidic hydrogen’s (pKa

Identify all the acidic hydrogen’s (pKa < 25) in the following molecules:

Identify all the acidic hydrogen’s (pKa < 25) in the

Q:Rank the following compounds in order of increasing acidity:

Rank the following compounds in order of increasingacidity:

Rank the following compounds in order of increasing acidity:

Q:Write resonance structures for the following anions:

Write resonance structures for the followinganions:

Write resonance structures for the following anions:

Q:Predict the product(s) of the following reactions: 2

Predict the product(s) of the followingreactions:

Predict the product(s) of the following reactions: 2

Q:Which, if any, of the following compounds can be prepared

Which, if any, of the following compounds can be prepared by a malonic ester synthesis? Show the alkyl halide you would use in each case.

(a) Ethyl pentanoate

(b) Ethyl 3-rnethylbutanoate

(c) Ethyl 2-methylbutanoate

(d) Ethyl 2, 2-dimethylpropanoate

Q:Which, if any, of the following compounds can be prepared by

Which, if any, of the following compounds can be prepared by an acetoacetic ester synthesis?Explain.

Which, if any, of the following compounds can be prepared by

Q:How would you prepare the following ketones using an acetoacetic

How would you prepare the following ketones using an acetoacetic estersynthesis?

How would you prepare the following ketones using an acetoacetic

Q:How would you prepare the following compounds using either an

How would you prepare the following compounds using either an acetoacetic ester synthesis or a malonic estersynthesis?

How would you prepare the following compounds using either an

Q:Which of the following substances would undergo the halo form

Which of the following substances would undergo the halo form reaction?

(a) CH3COCH3

(b) Acetophenone

(c) CH3CH2CHO

(d) CH3CO2H

(e) CH3C ≡N

Q:One way to determine the number of acidic hydrogen’s in

One way to determine the number of acidic hydrogen’s in a molecule is to treat the compound with NaOD in D20, isolate the product, and determine its molecular weight by mass spectrometry. For example, if Cyclohexanone is treated with NaOD in D20, the product has MW = 102. Explain how this method works.

Q:Base treatment of the following α, β-unsaturated carbo

Base treatment of the following α, β-unsaturated carbonyl compound yields an anion by removal of H from the y carbon. Why is hydrogen’s on the y carbon atom acidic?

Base treatment of the following α, β-unsaturated carbo

Q:Treatment of 1-phenyl-2-propenone with a strong base such as LDA

Treatment of 1-phenyl-2-propenone with a strong base such as LDA does not yield an anion, even though it contains a hydrogen on the carbon atom next to the carbonyl group.Explain.

Treatment of 1-phenyl-2-propenone with a strong base such as LDA

Q:When optically active (R)-2-rnethylcyclohexanone is treated with

When optically active (R)-2-rnethylcyclohexanone is treated with either aqueous base or acid, racemization occurs. Explain.

Q:Would you expect optically active (S)-3-methylcyclohexanonc to b

Would you expect optically active (S)-3-methylcyclohexanonc to be race-mized on acid or base treatment in the same way as 2-methylcyclohexanonc (Problem 22.32) Explain.

Q:When an optically active carboxylic acid such as (R)-2-phcnylpro

When an optically active carboxylic acid such as (R)-2-phcnylpropanoic acid is brominated under Hell—Volhard—Zelinskii conditions, is the product optically active or racemic? Explain.

Q:Fill in the reagents a that are missing from the

Fill in the reagents a that are missing from the followingscheme:

Fill in the reagents a that are missing from the

Q:Non-conjugated β, γ-un-saturated ketones, such as 3-cy

Non-conjugated β, γ-un-saturated ketones, such as 3-cyclohexenonc, arc in an acid-catalyzed equilibrium with their conjugated a,-unsaturated isomers propose a mechanism for this isomerization.

Non-conjugated β, γ-un-saturated ketones, such as 3-cy

Q:The inter conversion of unsaturated ketones described in Problem

The inter conversion of unsaturated ketones described in Problem 22.36 is also catalyzed by base. Explain.

Q:An interesting consequence of the base-catalyzed isomerization o

An interesting consequence of the base-catalyzed isomerization of unsaturated ketones described in Problem 22.37 is that 2-substituted 2-cyclo- pentenones can be inter converted with 5-substituted 2-cyclopenlenones. Propose a mechanism (or thisisomerization.

An interesting consequence of the base-catalyzed isomerization o

Q:Although 2-substituled 2-cyclopentenones are in a base-catalyzed

Although 2-substituled 2-cyclopentenones are in a base-catalyzed equilibrium with their 5-substituted 2-cyclopentenone isomers (Problem 22.38), the analogous isomerization is not observed for 2-substituted 2-cyclohexenones.Explain.

Although 2-substituled 2-cyclopentenones are in a base-catalyzed

Q:Using curved arrows, propose a mechanism for the following reaction,

Using curved arrows, propose a mechanism for the following reaction, one of the steps in the metabolism of the amino acidalanine.

Using curved arrows, propose a mechanism for the following reaction,

Q:Using curved arrows, propose a mechanism for the following reaction, one

Using curved arrows, propose a mechanism for the following reaction, one of the steps in the biosynthesis of the amino acidtyrosine.

Using curved arrows, propose a mechanism for the following reaction, one

Q:All attempts to isolate primary and secondary nitroso compounds

All attempts to isolate primary and secondary nitroso compounds result only in the formation of oximes. Tertiary nitroso compounds, however, are stable.Explain.

All attempts to isolate primary and secondary nitroso compounds

Q:How flow might you convert geraniol into either ethyl geranylace

How flow might you convert geraniol into either ethyl geranylacetate orgeranylacetone?

How flow might you convert geraniol into either ethyl geranylace

Q:How would you synthesize the following compounds from Cyclohexanone? More than

How would you synthesize the following compounds from Cyclohexanone? More than one step may berequired.

How would you synthesize the following compounds from Cyclohexanone? More than

Q:The two isomers cis- and trans-4-tert-butyl-2-methylcyclohexanon

The two isomers cis- and trans-4-tert-butyl-2-methylcyclohexanone are inter-converted by base treatment. Which isomer do you think is more stable, and why?

Q:The following synthetic routes are incorrect. What is wrong with

The following synthetic routes are incorrect. What is wrong witheach?

The following synthetic routes are incorrect. What is wrong with

Q:At tempted Grignard reaction of Cyclohexanone with tert-butyl ma

At tempted Grignard reaction of Cyclohexanone with tert-butyl magnesium bromide gives only about 1% yield of the expected addition product along with 99% un-reacted Cyclohexanone. If D3O+ is added to the reaction mixture after a suitable period, however, the “un-reacted” Cyclohexanone is found to have one deuteriurn atom incorporated into it. Explain

At tempted Grignard reaction of Cyclohexanone with tert-butyl ma

Q:One of the later steps in glucose biosynthesis is the

One of the later steps in glucose biosynthesis is the isomerization of fructose 6-phosphate to glucose 6-phosphate. Propose a mechanism, using acid or base catalysis asneeded.

One of the later steps in glucose biosynthesis is the

Q:The Favorskii reaction involves treatment of with base to yield

The Favorskii reaction involves treatment of an α-bromo ketone with base to yield a ring-contracted product. For example, reaction of 2-bromocyclo-hexanone with aqueous NaOH yields Cyclopentanecarboxylic acid. Propose a mechanism.

The Favorskii reaction involves treatment of with base to yield

Q:Treatment of a cyclic ketone with diazomethane is a method

Treatment of a cyclic ketone with diazomethane is a method for accomplishing a ring-expansion reaction. For example, treatment of Cyclohexanone with diazomethane yields Cycloheptanone. Propose amechanism.

Treatment of a cyclic ketone with diazomethane is a method

Q:Ketones react slowly with benzeneselenenyl chloride in the

Ketones react slowly with benzeneselenenyl chloride in the presence of HCl to yield α-phenylselcno ketones. Propose a mechanism for this acid-catalyzed a-substitution reaction.

Ketones react slowly with benzeneselenenyl chloride in the

Q:Pentobarbital, marketed under the name Nembutal, is a barbiturat

Pentobarbital, marketed under the name Nembutal, is a barbiturate used in treating insomnia. It is synthesized in three steps from diethyl malonate. Show how you would synthesize the dialkylated intermediate, and then propose a mechanism [or the reaction of that intermediate with urea to givepentobarbital.

Pentobarbital, marketed under the name Nembutal, is a barbiturat

Q:As far hack as the 16th century, South American Incas

As far hack as the 16th century, South American Incas chewed the leaves 01 the coca bush, Erythroxylon coca, to combat fatigue. Chemical studies of Erythroxylon coca by Friedrich Wohler in 1862 resulted in the discovery of cocaine, C17H21NO4, as the active component. Basic hydrolysis of cocaine leads to methanol, benzoic acid, and another compound called ecgonine, C9H15NO3. Oxidation of ecgonine with CrO3 yields a keto acid that readily loses CO2 on heating, giving tropinone.

(a) What is a likely structure for the keto acid?

(b) What is a likely structure for ecgonine, neglecting stereochemistry?

(c) What is a likely structure for cocaine, neglectingstereochemistry?

As far hack as the 16th century, South American Incas

Q:The final step in an attempted synthesis of laurene, a

The final step in an attempted synthesis of laurene, a hydrocarbon isolated from the marine alga Laurencia gianduliferu, involved the Wittig reaction shown. The product obtained, however, was not laurene but an isomer. Propose a mechanism to account for these unexpectedresults.

The final step in an attempted synthesis of laurene, a

Q:The key step in a reported laboratory synthesis of sativene,

The key step in a reported laboratory synthesis of sativene, a hydrocarbon isolated from the mold Helminthosporium sativum, involves the following base treatment of a keto tosylate. What kind of reaction is occurring? How would you complete thesynthesis?

The key step in a reported laboratory synthesis of sativene,

Q:Amino acids can he prepared by reaction of alkyl halides

Amino acids can he prepared by reaction of alkyl halides with diethyl acetamidomalonate, followed by heating the initial alkylation product with aqueous lid. Show how you would prepare alanine, CH3CH(NH2) CO2H, one of the twenty amino acids found in proteins, and propose a mechanism for acid-catalyzed conversion of the initial alkylation product to the aminoacid.

Amino acids can he prepared by reaction of alkyl halides

Q:Amino acids can also be prepared by a two-step sequence

Amino acids can also be prepared by a two-step sequence that involves hell— Volhard—Zelinskii reaction of a carboxylic acid followed by treatment with ammonia. Show how you would prepare Leucine, (CH3)2 CHCH2CH (NH2) CO2H, and identify the mechanism of the second step.

Amino acids can also be prepared by a two-step sequence

Q:Heating carvone with aqueous sulfuric acid converts it into Carv

Heating carvone with aqueous sulfuric acid converts it into Carvacrol. Propose a mechanism for theisomerization.

Heating carvone with aqueous sulfuric acid converts it into Carv

Q:Which of the following objects are chiral? (a) Screwdriver (b)

Which of the following objects are chiral?

(a) Screwdriver

(b) Screw

(c) Beanstalk

(d) Shoe

Q:Identify the chirality centers in the following molecules. Build

Identify the chirality centers in the following molecules. Build molecular models if you needhelp.

Identify the chirality centers in the following molecules. Build

Q:Alanine, an amino add found in proteins, is chiral. Draw

Alanine, an amino add found in proteins, is chiral. Draw the two enantiorners of ala- nine using the standard convention of solid, wedged, and dashedlines.

Alanine, an amino add found in proteins, is chiral. Draw

Q:Identify the chirality centers in the following molecules (yello

Identify the chirality centers in the following molecules (yellow-green = Cl, pale yellow =F):

Identify the chirality centers in the following molecules (yello

Q:Is cocaine (Worked Example 9.2) dextrorotatory or levorotatory?

Is cocaine (Worked Example 9.2) dextrorotatory or levorotatory?

Q:A 1.50 g sample of coniine, the toxic extract of poison hemlock

A 1.50 g sample of coniine, the toxic extract of poison hemlock, was dissolved in 10.0mL of ethanol and placed in a sample cell with a 5.00 cm path length. The observed rotation at the sodium D line was + 1.21°. Calculate [α]D for coniine.

Q:Assign priorities to the following sets of sub stituents: (a) –

Assign priorities to the following sets of sub stituents:

(a) – H, – OH, – CH2CH3, – CH2CH2OH

(b) – CO2H, – CO2CH3, – CH2OH, – OH

(c) – CN, – CH2NH2, – CH2NHCH3, – NH2

(d) – SH, – CH2SCH3, – CH3, —SSCH3

Q:Orient each of the following drawings so that the lowest-priority

Orient each of the following drawings so that the lowest-priority group is toward the rear, and then assign R or Sconfiguration:

Orient each of the following drawings so that the lowest-priority

Q:Assign R or S configuration to the chirality center 4

Assign R or S configuration to the chirality center in each of the followingmolecules:

Assign R or S configuration to the chirality center 4

Q:Draw a tetrahedral representation of (S)-2-pentanol (2-hydroxype

Draw a tetrahedral representation of (S)-2-pentanol (2-hydroxypentane).

Q:Assign R or S configuration to the chirality center in

Assign R or S configuration to the chirality center in the following molecular model of the amino acid methionine (blue = N, yellow =S):

Assign R or S configuration to the chirality center in

Q:One of the following molecules (a)—(d) is D-erythrose 4-phosphat

One of the following molecules (a)—(d) is D-erythrose 4-phosphate, an intermediate in the Calvin photosynthetic cycle by which plants incorporate CO2 into carbohydrates. If D-erythrose 4-phosphate has R stereochemistry at both chirality centers, which of the structures is it? Which of the remaining three structures is the enantiomer of D-erythrose 4-phosphate, and which are diastereomers?

Q:Chloramphenicol, a powerful antibiotic isolated in 1949 from the

Chloramphenicol, a powerful antibiotic isolated in 1949 from the Streptomyces Venezuelae bacterium, is active against a broad spectrum of bacterial infections and is centers in Chloramphenicol.

Chloramphenicol, a powerful antibiotic isolated in 1949 from the

Q:Assign R, S configuration to each chirality center in the

Assign R, S configuration to each chirality center in the following molecular model of the amino acid isoleucine (blue =N):

Assign R, S configuration to each chirality center in the

Q:Which of the following structures represent meso compounds?

Which of the following structures represent mesocompounds?

Which of the following structures represent meso compounds?

Q:Which of the following have a meso form? (Recall that

Which of the following have a meso form? (Recall that the -ol suffix refers to an alcohol, Roll.)

(a) 2, 3-Butanediol

(b) 2, 3-Pentanediol

(c) 2,4-Pentanediol

Q:Does the following structure represent a meso compound? If so,

Does the following structure represent a meso compound? If so, indicate the symmetryplane.

Q:Suppose that acetic acid (CH3CO2H) reacts with (S)-2-butanol to

Suppose that acetic acid (CH3CO2H) reacts with (S)-2-butanol to form an ester (see Worked Example 9.6). What stereochemistry would you expect the product(s) to have? What is the relationship of theproducts?

Q:What stereoisomers would result from reaction of (±)-lactic acid

What stereoisomers would result from reaction of (±)-lactic acid with (S)-1-phenyl- ethylamine, and what is the relationship between them?

Q:What kinds of isomers are the following pairs? (a) (S)-5-Chloro-

What kinds of isomers are the following pairs?

(a) (S)-5-Chloro-2-hexene and Chiorocyclohexane

(b) (2R, 3R)-Dibromopentane and (2S, 3R)-dibromopentane

Q:What products are formed from acid-catalyzed hydration of racemi

What products are formed from acid-catalyzed hydration of racemic (±)-4-methyl- 1-hexenc? What can you say about the relative amounts of the products? Is the product mixture optically active?

Q:What products are formed from hydration of 4-methylcyclopentene?

What products are formed from hydration of 4-methylcyclopentene? What can you say about the relative amounts of the products?

Q:Identify the indicated hydrogen’s in the following molecules as pro-R 51279

Identify the indicated hydrogen’s in the following molecules as pro-R or pro-S:

Identify the indicated hydrogen’s in the following molecules as pro-R 51279

Q:Identify the indicated faces of carbon atoms in the following

Identify the indicated faces of carbon atoms in the following molecules as Re orSi:

Identify the indicated faces of carbon atoms in the following

Q:Lactic acid buildup in tired muscles results from reduction of

Lactic acid buildup in tired muscles results from reduction of pyruvate. If the reaction occurs from the Re face, what is the stereochemistry of theproduct?

Lactic acid buildup in tired muscles results from reduction of

Q:The aconitase-catalyzed addition of water to cis-aconitate in th

The aconitase-catalyzed addition of water to cis-aconitate in the citric acid cycle occurs with the following stereochemistry. Does the addition of the OH group occur on the Re or the Si face of the substrate? What about the addition of the H? Does the reaction have syn or antistereochemistry?

The aconitase-catalyzed addition of water to cis-aconitate in th

Q:Which of the following structures are identical? (Yellow-green =

Which of the following structures are identical? (Yellow-green =Cl)

Which of the following structures are identical? (Yellow-green =

Q:A Assign R or S configuration to the chirality centers

A Assign R or S configuration to the chirality centers in the following molecules (blue =N):

A Assign R or S configuration to the chirality centers

Q:Which, if any, of the following structures represent meso compou

Which, if any, of the following structures represent meso compounds? (Blue = N, yellow-green =Cl.)

Which, if any, of the following structures represent meso compou

Q:A Assign R or S configuration to each chirality center

A Assign R or S configuration to each chirality center in pseudoephedrine, an over-the-counter decongestant found in cold remedies (blue =N).

A Assign R or S configuration to each chirality center

Q:Which of the following compounds are chiral? Draw them, and

Which of the following compounds are chiral? Draw them, and label the chirality centers.

(a) 2, 4-Dimethylheptane

(b) 5-Ethyl-3, 3-dimethylheptane

(c) cis-l, 4-Dichlorocyclohexane

(d) 4, 5-Dimethyl-2, 6-octadiyne

Q:A Draw chiral molecule that meet the following descriptions:

A Draw chiral molecule that meet the following descriptions:

(a) A chloro alkane, C5H11C1

(b) An alcohol, C6H14O

(c) An alkene, C6H12

(d) An alkane, C8H18

Q:A Eight alcohols have the formula C5H120. Draw them. Which

A Eight alcohols have the formula C5H120. Draw them. Which are chiral?

Q:Draw the nine chiral molecules that have the formula C6H13Br.

Draw the nine chiral molecules that have the formula C6H13Br.

Q:Draw compounds that fit the following descriptions: (a) A chiral

Draw compounds that fit the following descriptions:

(a) A chiral alcohol with four carbons

(h) A chiral carboxylic acid with the formula C5H10O2

(c) A compound with two chirality centers

(d) A chiral aldehyde with the formula C3H5BrO

Q:Which of the following objects arc chiral? (a) A basketball (b)

Which of the following objects arc chiral?

(a) A basketball

(b) A fork

(c) A wine glass

(d) A golf club

(e) A monkey wrench

(f) A snowflake

Q:Erythronolide B is the biological precursor of erythromycin, a b

Erythronolide B is the biological precursor of erythromycin, a broad-spectrum antibiotic. How many chirality centers does Erythronolide Bhave?

Erythronolide B is the biological precursor of erythromycin, a b

Q:Draw examples of the following: (a) A meso compound with the

Draw examples of the following:

(a) A meso compound with the formula C8H18

(b) A meso compound with the formula C9H20

(c) A compound with two chirality centers, one R and the other S

Q:What is the relationship between the specific rotations of (2R,

What is the relationship between the specific rotations of (2R, 3R)-dichloro- pentane and (2S, 3S)-dichloro pentane? Between (2R, 35)-dichloro pentane and (2R, 3R)-dichloro pentane?

Q:What is the stereo chemical configuration of the enantiomer of

What is the stereo chemical configuration of the enantiomer of (2S, 4R)-2, 4-oclanediol?

Q:What are the stereo chemical configurations of the two diastereo

What are the stereo chemical configurations of the two diastereomers of (25, 4R) -2, 4-octanediol?

Q:Orient each of the following drawings so that the lowest-priority group

Orient each of the following drawings so that the lowest-priority group is toward the rear, and then assign R or Sconfiguration:

Q:Assign Cahn—In gold-Prelog priorities to the following sets of s

Assign Cahn—In gold-Prelog priorities to the following sets of sub-stituents:

Q:Assign R or S configurations to the chirality centers in 51300

Assign R or S configurations to the chirality centers in the followingmolecules:

Assign R or S configurations to the chirality centers in 51300

Q:Assign R or S configuration to each chirality center 2

Assign R or S configuration to each chirality center in the followingmolecules:

Assign R or S configuration to each chirality center 2

Q:Assign R or S configuration to each chirality center 3

Assign R or S configuration to each chirality center in the following biologicalmolecules:

Assign R or S configuration to each chirality center 3

Q:Draw tetrahedral representations of the following molecules: (a)

Draw tetrahedral representations of the following molecules:

(a) (S)-2-Chlorohutane

(b) (R)-3-Chloro-1-pentene

Q:Draw tetrahedral representations of the two enantiomers of the a

Draw tetrahedral representations of the two enantiomers of the amino acid cysteine, HSCH2CH (NH2) CO2H, and identify each as R or S.

Q:The naturally occurring form of the amino acid cysteine (Problem

The naturally occurring form of the amino acid cysteine (Problem 9.48) has the S configuration at its chirality center. On treatment with a mild oxidizing agent, two cysteines join to give cystine, a disulfide. Assuming that the chirality center is not affected by the reaction, is cystine optically active?

Q:Which of the following pairs of structures represent the same

Which of the following pairs of structures represent the same enantiomer, and which represent different enantiomers?

Q:Assign R or S configuration to each chirality

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