Question 1

The accompanying diagram implies that:

Accepted Answer

A)  the formation of B from A would be favored at high temperature. 
B)  the more stable product forms more rapidly from the intermediate species. 
C)  the formation of B from the intermediate is the rate-limiting step in the transformation of A into B 
D)  the formation of B from A is not a concerted reaction. 
E)  All of the above statements are true. 
A)  the formation of B from A would be favored at high temperature. 
B)  the more stable product forms more rapidly from the intermediate species. 
C)  the formation of B from the intermediate is the rate-limiting step in the transformation of A into B 
D)  the formation of B from A is not a concerted reaction. 
E)  All of the above statements are true.

Question 2

Which of the following dieneophiles is most reactive in a Diels-Alder reaction:

Accepted Answer

A)  I 
B)  II 
C)  III 
D)  IV 
E)  V 
A)  I 
B)  II 
C)  III 
D)  IV 
E)  V

Question 3

Which diene would be least reactive toward Diels-Alder addition of maleic anhydride?

Accepted Answer

A)  I 
B)  II 
C)  III 
D)  IV 
E)  V 
A)  I 
B)  II 
C)  III 
D)  IV 
E)  V

Question 4

From the standpoint of reactivity,which is the poorest choice of dienophile to react with 2,3-dimethyl-1,3-butadiene in a Diels-Alder reaction?

Accepted Answer

A)  I 
B)  II 
C)  III 
D)  IV 
E)  V 
A)  I 
B)  II 
C)  III 
D)  IV 
E)  V

Question 5

Which alkene would you expect to be most stable?

Accepted Answer

A)  CH2=CHCH2CH2CH=CH2 
B) 
  
C) 
  
D) 
  
E) 
  
A)  CH2=CHCH2CH2CH=CH2 
B) 
  
C) 
  
D) 
  
E)

Question 6

Which is the major product of the following reaction?

Accepted Answer

A)  I 
B)  II 
C)  III 
D)  IV 
E)  V 
A)  I 
B)  II 
C)  III 
D)  IV 
E)  V

Question 7

Conjugated dienes routinely undergo 1,2 and 1,4 addition reactions with a variety of electrophilic reagents;this suggests that ___________ are likely intermediates during these reactions.

Accepted Answer

allylic ca

Question 8

Which diene and dienophile would you choose to synthesize the following compound?

Accepted Answer

A)  I 
B)  II 
C)  III 
D)  IV 
E)  None of these 
A)  I 
B)  II 
C)  III 
D)  IV 
E)  None of these

Question 9

Which of the following would afford a synthesis of the following compound?

Accepted Answer

A)  I 
B)  II 
C)  III 
D)  IV 
E)  None of these 
A)  I 
B)  II 
C)  III 
D)  IV 
E)  None of these

Question 10

Which of the following dienes would you expect to be the most stable?

Accepted Answer

A)  CH3CH2CH=CHCH2CH=CHCH3 
B)  CH3CH=CHCH=CHCH2CH3 
C)  CH2=CHCH2CH2CH2CH=CH2 
D)  CH2=CHCH=CHCH2CH2CH3 
E)  CH3CH=C(CH3)CH=CHCH2CH3 
A)  CH3CH2CH=CHCH2CH=CHCH3 
B)  CH3CH=CHCH=CHCH2CH3 
C)  CH2=CHCH2CH2CH2CH=CH2 
D)  CH2=CHCH=CHCH2CH2CH3 
E)  CH3CH=C(CH3)CH=CHCH2CH3

Question 11

Which of these conjugated dienes can undergo a Diels-Alder reaction?

Accepted Answer

A)  I 
B)  II 
C)  III 
D)  IV 
E)  All of the above 
A)  I 
B)  II 
C)  III 
D)  IV 
E)  All of the above

Question 12

Complete the following sequence of reactions,giving structural details of all key intermediates.

Accepted Answer

The answer of Complete the following sequence of reactions,giving structural...

Question 13

Which diene and dienophile would you use to prepare the following molecule using a Diels-
Alder cycloaddition reaction:

Accepted Answer

The answer of Which diene and dienophile would you use...

Question 14

Which is an untrue statement concerning the Diels-Alder reaction?

Accepted Answer

A)  The reaction is a syn addition. 
B)  The diene must be in the s-cis conformation to react. 
C)  Most Diels-Alder reactions are reversible. 
D)  Generally,the adduct formed most rapidly is the exo product. 
E)  Electron donating groups on the diene and electron withdrawing groups on the dieneophile favor adduct formation. 
A)  The reaction is a syn addition. 
B)  The diene must be in the s-cis conformation to react. 
C)  Most Diels-Alder reactions are reversible. 
D)  Generally,the adduct formed most rapidly is the exo product. 
E)  Electron donating groups on the diene and electron withdrawing groups on the dieneophile favor adduct formation.

Question 15

An unsaturated product results from the reaction of cyclohexene with which of these?

Accepted Answer

A)  Br2/CCl4 at 25  $\degree$C 
B)  NBS/CCl4,ROOR 
C)  HCl,ROOR 
D)  HCl,no peroxides 
E)  More than one of these 
A)  Br2/CCl4 at 25  $\degree$C 
B)  NBS/CCl4,ROOR 
C)  HCl,ROOR 
D)  HCl,no peroxides 
E)  More than one of these

Question 16

What is the product of the following reaction?

Accepted Answer

A)  I 
B)  II 
C)  III 
D)  IV 
E)  V 
A)  I 
B)  II 
C)  III 
D)  IV 
E)  V

Question 17

Select the structure of the conjugated diene.

Accepted Answer

A)  I 
B)  II 
C)  III 
D)  IV 
E)  V 
A)  I 
B)  II 
C)  III 
D)  IV 
E)  V

Question 18

There are three types of polyenes (molecules containing two or more double bonds).They are: _________________.

Accepted Answer

conjugated

Question 19

Which of these dienes can undergo the Diels-Alder reaction?

Accepted Answer

A)  1,3-Pentadiene 
B)  1,4-Pentadiene 
C)  1,2-Butadiene 
D)  1,4-Cyclohexadiene 
E)  All of the above can undergo the Diels-Alder reaction 
A)  1,3-Pentadiene 
B)  1,4-Pentadiene 
C)  1,2-Butadiene 
D)  1,4-Cyclohexadiene 
E)  All of the above can undergo the Diels-Alder reaction

Question 20

Which would be the best synthesis?

Accepted Answer

A) 
  
B) 
  
C) 
  
D) 
  
E) 
  
A) 
  
B) 
  
C) 
  
D) 
  
E)

Exam 13: Conjugated Unsaturated Systems

The accompanying diagram implies that:

Which of the following dieneophiles is most reactive in a Diels-Alder reaction:

Which diene would be least reactive toward Diels-Alder addition of maleic anhydride?

From the standpoint of reactivity,which is the poorest choice of dienophile to react with 2,3-dimethyl-1,3-butadiene in a Diels-Alder reaction?

Which alkene would you expect to be most stable?

Which is the major product of the following reaction?

Conjugated dienes routinely undergo 1,2 and 1,4 addition reactions with a variety of electrophilic reagents;this suggests that ___________ are likely intermediates during these reactions.

Which diene and dienophile would you choose to synthesize the following compound?

Which of the following would afford a synthesis of the following compound?

Which of the following dienes would you expect to be the most stable?

Which of these conjugated dienes can undergo a Diels-Alder reaction?

Complete the following sequence of reactions,giving structural details of all key intermediates.

Which diene and dienophile would you use to prepare the following molecule using a Diels- Alder cycloaddition reaction:

Which is an untrue statement concerning the Diels-Alder reaction?

An unsaturated product results from the reaction of cyclohexene with which of these?

What is the product of the following reaction?

Select the structure of the conjugated diene.

There are three types of polyenes (molecules containing two or more double bonds).They are: _________________.

Which of these dienes can undergo the Diels-Alder reaction?

Which would be the best synthesis?

Carbon Compounds and Chemical Bonds

Representative Carbon Compounds: Functional Groups, Intermolecular Forces, and Infrared Ir Spectroscopy

An Introduction to Organic Reactions: Acids and Bases

Alkanes: Nomenclature, Conformational Analysis, and an Introduction to Synthesis

Stereochemistry: Chiral Molecules

Ionic Reactions - Nucleophilic Substitution and Elimination Reactions of Alkyl Halides

Alkenes and Alkynes I: Properties and Synthesis, Elimination Reactions of Alkyl Halides

Alkenes and Alkynes Ii: Addition Reactions

Nuclear Magnetic Resonance and Mass Spectrometry: Tools for Structure Determination

Radical Reactions

Alcohols and Ethers

Alcohols From Carbonyl Compounds Oxidation-Reduction and Organometallic Compounds

Aromatic Compounds

Reactions of Aromatic Compounds

Aldehydes and Ketones I Nucleophilic Addition to the Carbonyl Group

Aldehydes and Ketones Ii Aldol Reactions

Carboxylic Acids and Their Derivatives Nucleophilic Addition - Elimination at the Acyl Carbon

Synthesis and Reactions of Beta-Dicarbonyl Compounds: More Chemistry of Enolate Ions

Amines

Phenols and Aryl Halides: Nucleophilic Aromatic Substitution

Carbohydrates

Lipids

Amino Acids and Proteins

Nucleic Acids and Protein Synthesis

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