Question 1

What is (are) the major organic product(s) formed in the following reaction?

Accepted Answer

A) only 1 
B) only 1 and 3 
C) only 2 and 4 
D) only 1 and 4 
A) only 1 
B) only 1 and 3 
C) only 2 and 4 
D) only 1 and 4

Question 2

Electrophilic addition reaction of conjugated dienes that occur at high temperature and/or long reaction times (reversible conditions) are said to be under kinetic control.

Accepted Answer

A) True 
 B)False

Question 3

The following spectrum could arise from $\pi$ to $\pi$* transitions.

Accepted Answer

A) True 
 B)False

Question 4

What is the IUPAC name of the following compound?

Accepted Answer

A) (R)-3-vinyl-1-butene 
B) 3-methyl-1,5-pentadiene 
C) 3-methyl-1,4-pentadiene 
D) (R)-3-methyl-1,4-pentadiene 
A) (R)-3-vinyl-1-butene 
B) 3-methyl-1,5-pentadiene 
C) 3-methyl-1,4-pentadiene 
D) (R)-3-methyl-1,4-pentadiene

Question 5

Which of the following electronic transitions is apparent in the ultraviolet-visible spectrum of 1,3-butadiene?

Accepted Answer

A) "n $\rarr$ $\pi$*" 
B) "$\pi$ $\rarr$ $\pi$ *" 
C) " $\sigma$$\rarr$ $\pi$ *" 
D) " $\sigma$ $\rarr$ $\pi$" 
A) "n $\rarr$ $\pi$*" 
B) "$\pi$ $\rarr$ $\pi$ *" 
C) " $\sigma$$\rarr$ $\pi$ *" 
D) " $\sigma$ $\rarr$ $\pi$"

Question 6

Which of the following is not a major organic product obtained from the addition of 1 mole of bromine to (E)-1,3-pentadiene?

Accepted Answer

A) (
E) -4,5-dibromo-2-pentene 
B) 3,4-dibromo-1-pentene 
C) (
E) -1,4-dibromo-2-pentene 
D) (
E) -1,2-dibromo-2-pentene 
A) (
E) -4,5-dibromo-2-pentene 
B) 3,4-dibromo-1-pentene 
C) (
E) -1,4-dibromo-2-pentene 
D) (
E) -1,2-dibromo-2-pentene

Question 7

Sigmatropic shifts, cycloaddition reactions and anuulation reactions are all examples of pericyclic reactions.

Accepted Answer

A) True 
 B)False

Question 8

For a diene to undergo a Diels-Alder reaction it must be able to adopt an s-trans conformation.

Accepted Answer

A) True 
 B)False

Question 9

What is (are) the major organic product(s) formed in the following reaction?

Accepted Answer

A) only 1 
B) only 3 
C) only 1 and 3 
D) only 2 and 4 
A) only 1 
B) only 3 
C) only 1 and 3 
D) only 2 and 4

Question 10

The conjugated portion of the following molecule is circled.

Accepted Answer

A) True 
 B)False

Question 11

What is the thermodynamic product obtained from the addition of 1 mole of bromine to 1,3-butadiene?

Accepted Answer

A) 3,4-dibromo-1-butene 
B) (
E) -1,4-dibromo-2-butene 
C) (Z)-1,4-dibromo-2-butene 
D) (Z)-2,3-dibromo-2-butene 
A) 3,4-dibromo-1-butene 
B) (
E) -1,4-dibromo-2-butene 
C) (Z)-1,4-dibromo-2-butene 
D) (Z)-2,3-dibromo-2-butene

Question 12

Consider the reaction below to answer the following question(s):   Enter the appropriate letter in the blank for each the following statements.
-The product that results from 1,4-addition is _____.

Accepted Answer

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

Question 13

For Diels-Alder cycloaddition reactions to take place most rapidly and in highest yield a dienophile must be substituted with electron-donating groups.

Accepted Answer

A) True 
 B)False

Question 14

What is the major organic product obtained from the following reaction?

Accepted Answer

The answer of What is the major organic product obtained...

Question 15

Consider the reaction below to answer the following question(s).   Fill in the blank in the question with the appropriate letter.
-The dienophile in the reaction is ____.

Accepted Answer

A) A 
B) B 
C) C 
A) A 
B) B 
C) C

Question 16

What is (are) the major organic product(s) formed in the following reaction?

Accepted Answer

A) only 1 
B) only 2 
C) only 3 
D) 1, 2 and 3 
A) only 1 
B) only 2 
C) only 3 
D) 1, 2 and 3

Question 17

Consider the reaction below to answer the following question(s):   Enter the appropriate letter in the blank for each the following statements.
-Based on the following table.
Compound
$\lambda$max (nm)
W
190
X
340
Y
560
Z
250
Compound ______ has the largest energy difference between the HOMO and LUMO.

Accepted Answer

Question 18

Which of the following energy diagrams represents the electronic state of butadiene after absorption of radiation?

Accepted Answer

A) 1 
B) 2 
C) 3 
D) 4 
A) 1 
B) 2 
C) 3 
D) 4

Question 19

The conjugated portion of the following molecule is circled.

Accepted Answer

A) True 
 B)False

Question 20

What are the units of $\lambda$max in ultraviolet-visible spectroscopy?

Accepted Answer

A) J.mol-1 
B) M-1 
C) nm 
D) none, $\lambda$max is a dimensionless quantity 
A) J.mol-1 
B) M-1 
C) nm 
D) none, $\lambda$max is a dimensionless quantity

Exam 20: Dienes, Conjugated Systems, and Pericyclic Reactions

What is (are) the major organic product(s) formed in the following reaction?

Electrophilic addition reaction of conjugated dienes that occur at high temperature and/or long reaction times (reversible conditions) are said to be under kinetic control.

The following spectrum could arise from π\piπ to π\piπ * transitions.

What is the IUPAC name of the following compound?

Which of the following electronic transitions is apparent in the ultraviolet-visible spectrum of 1,3-butadiene?

Which of the following is not a major organic product obtained from the addition of 1 mole of bromine to (E)-1,3-pentadiene?

Sigmatropic shifts, cycloaddition reactions and anuulation reactions are all examples of pericyclic reactions.

For a diene to undergo a Diels-Alder reaction it must be able to adopt an s-trans conformation.

What is (are) the major organic product(s) formed in the following reaction?

The conjugated portion of the following molecule is circled.

What is the thermodynamic product obtained from the addition of 1 mole of bromine to 1,3-butadiene?

Consider the reaction below to answer the following question(s): Enter the appropriate letter in the blank for each the following statements. -The product that results from 1,4-addition is _____.

For Diels-Alder cycloaddition reactions to take place most rapidly and in highest yield a dienophile must be substituted with electron-donating groups.

What is the major organic product obtained from the following reaction?

Consider the reaction below to answer the following question(s). Fill in the blank in the question with the appropriate letter. -The dienophile in the reaction is ____.

What is (are) the major organic product(s) formed in the following reaction?

Which of the following energy diagrams represents the electronic state of butadiene after absorption of radiation?

The conjugated portion of the following molecule is circled.

What are the units of λ\lambdaλ max in ultraviolet-visible spectroscopy?

Covalent Bonding and Shapes of Molecules

Alkanes and Cycloalkanes

Stereoisomerism and Chirality

Acids and Bases

Alkenes: Bonding, Nomenclature, and Properties

Reactions of Alkenes

Alkynes

Haloalkanes, Halogenation, and Radical Reactions

Nucleophilic Substitution and Beta-Elimination

Alcohols

Ethers, Epoxides, and Sulfides

Infrared Spectroscopy

Nuclear Magnetic Resonance Spectroscopy

Mass Spectrometry

An Introduction to Organometallic Compounds

Aldehydes and Ketones

Carboxylic Acids

Functional Derivatives of Carboxylic Acids

Enolate Anions and Enamines

Benzene and the Concept of Aromaticity

Reactions of Benzene and Its Derivatives

Amines

Catalytic Carbon-Carbon Bond Formation

Carbohydrates

Lipids

Amino Acids and Proteins

Nucleic Acids

Organic Polymer Chemistry

Filters

The following spectrum could arise from $\pi$ to $\pi$ * transitions. $The following spectrum could arise from \pi to \pi * transitions.$

What are the units of $\lambda$ _max in ultraviolet-visible spectroscopy?