klein chapter 12 problems : alcohols and phenols

Dr. Peter Norris OChem 2

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Klein Chapter 12 Problems : Alcohols and Phenols

1. Provide each of the following molecules with an acceptable name. You may use IUPAC or

“common” names for substituents. Be sure to include any stereochemical descriptors where needed

(R/S, cis/trans).

2. Give the (major and minor) product(s) expected to be formed from each step under each of the

following sets of reaction conditions. Include any stereochemical issues that might be important in

each outcome.

3. Provide detailed mechanisms for each of the following conversions that include all important

resonance structures for any intermediates that are formed. Include any stereochemical changes that

might take place.

4. Rank the following molecules in terms of their increasing acid strength; 1 = weakest acid, 4 =

strongest acid. Give brief explanations for your choices.


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Klein Chapter 12 Problems : Alcohols and Phenols - Answers

1. “Provide each of the following molecules with an acceptable name. You may use IUPAC or “common”

names for substituents. Be sure to include any stereochemical descriptors where needed (R/S, cis/trans).”

2. “Give the (major and minor) product(s) expected to be formed from each step under each of the following

sets of reaction conditions. Include any stereochemical issues that might be important in each outcome.”

3. “Provide detailed mechanisms for the following conversions that include all important resonance structures

for any intermediates that are formed. Include any stereochemical changes that might take place.”


2

4. “Rank the following molecules in terms of their increasing acid strength; 1 = weakest acid, 4 = strongest

acid. Give brief explanations for your choices.”

1 is a simple alcohol in which the conjugate base will have the negative charge localized on O; 2 is an enol so the conjugate

base charge will be stabilized by resonance; 3 is a phenol so the conjugate base is stabilized significantly by delocalization

into the phenyl ring; 4 is a phenol with a strongly electron-withdrawing NO2 group that stabilizes better than CH3 in 3.


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Klein Chapter 13 Problems : Ethers & Epoxides ; Thiols & Sulfides

1. Provide each of the following ethers with an acceptable name. You may use IUPAC or “common” names for

substituents. Be sure to include any stereochemical descriptors where needed (R/S, cis/trans).

2. Give the (major and minor) product(s) expected to be formed from each step under each of the following sets

of reaction conditions. Include any stereochemical issues that might be important in each outcome.

3. Provide detailed mechanisms for each of the following conversions that include all important resonance

structures for any intermediates that are formed. Include any stereochemical changes that might take place.

4. Provide viable, efficient syntheses of the products shown from the starting materials provided in each case.

You may use any of the chemistry and reagents seen so far in Organic 1 and Organic 2.


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Klein Chapter 13 Problems : Ethers & Epoxides ; Thiols & Sulfides - Key

1. “Provide each of the following ethers with an acceptable name. You may use IUPAC or “common” names for

substituents. Be sure to include any stereochemical descriptors where needed (R/S, cis/trans).”

2. “Give the (major and minor) product(s) expected to be formed from each step under each of the following

sets of reaction conditions. Include any stereochemical issues that might be important in each outcome.”

3. “Provide detailed mechanisms for the following conversions that include all important resonance structures

for any intermediates that are formed. Include any stereochemical changes that might take place.”


2

4. “Provide viable, efficient syntheses of the products shown from the starting materials provided in each case.

You may use any of the chemistry and reagents seen so far in Organic 1 and Organic 2.”


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Klein Chapter 14 Problems : IR Spectroscopy & MS Spectrometry

1. In each of the following situations, which one of the molecules matches the given IR spectrum? Match as

many frequencies as you can from the spectroscopy sheet to back up your answers.

a)

b)

c)


2

2. In each of the following situations, which one of the molecules matches the given mass spectrum? Match as

many fragments as you can to back up your answers.

a)

b)

c)


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Klein Chapter 14 Problems : IR Spectroscopy & MS Spectrometry - Key

1. In each of the following situations, which one of the molecules matches the given IR spectrum? Match as

many frequencies as you can from the spectroscopy sheet to back up your answers.

a)

b)

c)


2

2. In each of the following situations, which one of the molecules matches the given mass spectrum? Match as

many fragments as you can to back up your answers.

a)

b)

c)


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Klein Chapter 15 Problems : Nuclear Magnetic Resonance Spectroscopy

1. In each of the following situations, which one of the molecules matches the given 1H NMR spectrum? Match

as many signals as you can from the spectroscopy sheet to back up your answers.

a)

b)


2

c)

d)

2. How many individual signals do you expect to appear in the 13C spectra of each of the following?


3

3. In each of the following situations, which one of the molecules matches the given 13C NMR spectrum? Match


a)

b)


4

c)

d)


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Klein Chapter 15 Problems : NMR Spectroscopy – Answers

1. In each of the following situations, which one of the molecules matches the given 1H NMR spectrum? Match


a)

b)


2

c)

d)

2. How many individual signals do you expect to appear in the 13C spectra of each of the following?


3

3. In each of the following situations, which one of the molecules matches the given 13C NMR spectrum? Match


a)

b)


4

c)

d)


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Klein Chapter 16 Problems : Conjugated Pi Systems & Pericyclic Reactions

1. For each of the following reactions, decide which product is major and which is minor and then provide a

mechanistic rationale for your choices that includes arrow pushing and discussions of any intermediate

structure or stereochemical factors necessary.

2. In each of the following instances, provide the major and minor products (where applicable) that you expect

to be formed under the conditions provided.

3. Within each pair of molecules below, which one do you expect to absorb at the longer wavelength in UV-

Visible spectroscopy? Briefly explain your choices.


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Klein Chapter 16 Problems : Conjugated Pi Systems - Answers

1. For each of the following reactions, decide which product is major and which is minor and then provide a

mechanistic rationale for your choices that includes arrow pushing and discussions of any intermediate

structure or stereochemical factors necessary.


2

2. In each of the following instances, provide the major and minor products (where applicable) that you expect

to be formed under the conditions provided.

3. Within each pair of molecules below, which one do you expect to absorb at the longer wavelength in UV-

Visible spectroscopy? Briefly explain your choices.


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Klein Chapter 17 Problems : Aromatic Compounds

1. Provide each of the following benzene derivatives with an acceptable name.

2. Using Huckel’s rule, indicate which of the following molecules are expected to be aromatic and which are

not.

3. Provide the major products that you expect to be formed under each of the following sets of reaction

conditions.


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Klein Chapter 17 Problems : Aromatic Compounds - Answers

1. “Provide each of the following benzene derivatives with an acceptable name.”

2. “Using Huckel’s rule, indicate which of the following molecules are expected to be aromatic and which are

not.”


2

3. “Provide the major products that you expect to be formed under each of the following sets of reaction

conditions.”


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Klein Chapter 18 Problems : Electrophilic Aromatic Substitution

1. Give the expected major products from each step of the following reaction sequences. Assume that you are able

to separate isomers when needed.

2. Provide reagents that would allow for each of the following transformations to be successful. Assume that you

are able to separate isomers when needed.


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Klein Chapter 18 Problems : EAS - Answers

1. Give the expected major products from each step of the following reaction sequences. Assume that you are able

to separate isomers when needed.


2

2. Provide reagents that would allow for each of the following transformations to be successful. Assume that you

are able to separate isomers when needed.


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Klein Chapter 19 Problems : Aldehydes and Ketones

1. Give the expected major products from each step of the following reaction sequences.

2. Give retrosynthetic analyses for the following molecules that go back to the given starting materials, and then

provide the synthesis in the forward direction. Assume you have access to the usual other reagents (HBr, HNO3,

NaBH4, etc.) in the lab.


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Klein Chapter 19 Problems : Aldehydes and Ketones - Answers

1. Give the expected major products from each step of the following reaction sequences.


2





3

Synthesis


4

Synthesis


5

Synthesis


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Klein Chapter 20 Problems : Carboxylic Acids & Derivatives




2. In the boxes provided, give the products from each step in the following “road-map” scheme. Predict the 1H

NMR spectrum of each of the organic products from each step.


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Klein Chapter 20 Problems : Carboxylic Acids & Derivs. – Answers




a.


2

b.

c.


3

d.


4

2. In the boxes provided, give the products from each step in the following “road-map” scheme. Predict the 1H

NMR spectrum of each of the organic products from each step.

7.26

7.19

7.26

7.66

7.66MgBr

02468PPM

7.18

7.22

7.18

7.44

7.44Br

02468PPM

7.66

7.79

7.66

8.21

8.21

O

OMgBr

02468PPM

7.66

7.79

7.66

8.21

8.21

12.74

O

OH

024681012PPM


5

7.56

7.66

7.56

8.05

8.05 3.89O

O

02468PPM

7.82

8.47 8.60

8.44 3.89

N+

O O-

O

O

02468PPM

7.64

8.19 8.25

7.93

1.30

1.30

OLi

N+

O O-

02468PPM

7.64

8.19 8.25

7.93

5.52

1.30

1.30

OH

N+

O O-

02468PPM


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Klein Chapter 21 Problems : Enols and Enolates

1. Give the major organic product(s) from each step of the following synthetic sequence.

2. In the boxes provided, give the products from each step in the following “road-map” scheme.


2

3. The polyether compound Chauncydermolide G (shown below) was recently isolated by Triplet Pharmaceuticals

Inc. and found to have promising antibiotic properties. In order to prove the structure unequivocally, a total

synthesis beginning with the shown starting material was carried out. Give structures for each of the products

in the synthetic sequence.


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Klein Chapter 21 Problems : Enols and Enolates – Answers


2. In the boxes provided, give the products from each step in the following “road-map” scheme.


2

3. The polyether compound chauncydermolide G (shown below) was recently isolated by Triplet Pharmaceuticals

Inc. and found to have promising antibiotic properties. In order to prove the structure unequivocally, a total

synthesis beginning with the shown starting material was carried out. Give structures for each of the products

in the synthetic sequence.


3


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Klein Chapter 22 Problems : Amines


2. Provide the major product from each step of the following reaction sequences.



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Klein Chapter 22 Problems : Amines - Answers




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Klein Chapter 23 Problems : Organometallics

1. Give the major organic polymeric product that is expected to be formed under the following ROMP conditions.

Hint: the more electron-rich alkene will open before the more electron-poor option.

2. Provide the major product that you expect to be formed under the following metathesis conditions.

3. Draw the major product expected to be formed under the following Stille conditions.

4. Provide the major product that you expect to be delivered from the following Negishi coupling.

5. Give the expected products from the following intramolecular metathesis process.

6. Give a structure for the product that will formed under the Suzuki conditions below.


1

Klein Chapter 23 Problems : Organometallics – Answers

1. Give the major organic polymeric product that is expected to be formed under the following ROMP conditions.

Hint: the more electron-rich alkene will open before the more electron-poor option.

2. Provide the major product that you expect to be formed under the following metathesis conditions.

3. Draw the major product expected to be formed under the following Stille conditions.

4. Provide the major product that you expect to be delivered from the following Negishi coupling.

5. Give the expected products from the following intramolecular metathesis process.

6. Give a structure for the product that will formed under the Suzuki conditions below.


1

Klein Chapters 24-26 Problems : Biomolecules

1. Suggest a mechanistic pathway for how D-Mannose, in which the C-2 OH group is axial, is able to convert to

D-Glucose, in which that OH group is equatorial. This occurs in vivo in enzymatic systems in which acid-

and/or base-catalysis is available.

2. In the presence of water and a Lewis acid (e.g. a proton from a carboxylic acid residue in an enzyme), the

nucleoside shown below is hydrolyzed to 2-deoxy-D-ribose and uracil products. Try to invoke a mechanistic

pathway for this type of hydrolysis could work, and how you get a mixture of anomers for the sugar.

3. Draw structures for all of the possible dipeptides that are formed when L-serine, L-alanine, and L-arginine are coupled

together in one single reaction flask. Then suggest how you would synthesize only H2N-L-serine – L-alanine-CO2H.

4. Suggest a mechanism for how D-Glucuronolactone (below) is converted in two steps to D-Glucuronic acid.

5. Work out the configurations (R/S, E/Z) for all stereocenters and alkenes in the lipid Prostaglandin F1.


1

Klein Chapters 24-26 Problems : Biomolecules – Answers

1. Suggest a mechanistic pathway for how D-Mannose, in which the C-2 OH group is axial, is able to convert to

D-Glucose, in which that OH group is equatorial. This occurs in vivo in enzymatic systems in which acid-

and/or base-catalysis is available.

2. In the presence of water and a Lewis acid (e.g. a proton from a carboxylic acid residue in an enzyme), the

nucleoside shown below is hydrolyzed to 2-deoxy-D-ribose and uracil products. Try to invoke a mechanistic

pathway for this type of hydrolysis could work, and how you get a mixture of anomers for the sugar.

3. Draw structures for all of the possible dipeptides that are formed when L-serine, L-alanine, and L-arginine are coupled

together in one single reaction flask. Then suggest how you would synthesize only H2N-L-serine – L-alanine-CO2H.


2

4. Suggest a mechanism for how D-Glucuronolactone (below) is converted in two steps to D-Glucuronic acid.

5. Work out the configurations (R/S, E/Z) for all stereocenters and alkenes in the lipid Prostaglandin F1.


1

Klein Chapter 27 Problems : Polymers

1. Suggest suitable monomer precursor(s) for synthesizing the following polymeric compounds. Then provide

the reaction conditions that will result in conversion of the monomer(s) into the polymer.

2. Circle the repeat units in each of the following polymeric compounds. Then comment on whether each of the

polymers will be expected be soluble in water or hexane.

3. For each of the following polymers, use the “square bracket” notation to indicate the repeat unit. Then suggest

whether each material is classified as being an addition or condensation polymer.


1

Klein Chapter 27 Problems : Polymers – Answers

1. Suggest suitable monomer precursor(s) for synthesizing the following polymeric compounds. Then provide

the reaction conditions that will result in conversion of the monomer(s) into the polymer.

2. Circle the repeat units in each of the following polymeric compounds. Then comment on whether each of the

polymers will be expected be soluble in water or hexane.

3. For each of the following polymers, use the “square bracket” notation to indicate the repeat unit. Then suggest

whether each material is classified as being an addition or condensation polymer.

klein chapter 12 problems : alcohols and phenols

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