Question 1

What is the systematic IUPAC name of the following compound?

Accepted Answer

A) (3S,4
E) -3-ethyl-3,4-dimethyl-1,4-hexadiene 
B) (3R,4
E) -3-ethyl-3,4-dimethyl-1,4-hexadiene 
C) (3S,4Z)-3-ethyl-3,4-dimethyl-1,4-hexadiene 
D) (3R,4Z)-3-ethyl-3,4-dimethyl-1,4-hexadiene 
A) (3S,4
E) -3-ethyl-3,4-dimethyl-1,4-hexadiene 
B) (3R,4
E) -3-ethyl-3,4-dimethyl-1,4-hexadiene 
C) (3S,4Z)-3-ethyl-3,4-dimethyl-1,4-hexadiene 
D) (3R,4Z)-3-ethyl-3,4-dimethyl-1,4-hexadiene

Question 2

What are the two major organic products obtained from the following reaction?

Accepted Answer

The answer of What are the two major organic products...

Question 3

Which of 1,3-cyclohexadiene and 1,4-cyclohexadiene has the greatest heat of hydrogenation (i.e., the most exothermic reaction with H2 in the presence of a catalyst). Provide a brief explanation for your choice ?

Accepted Answer

1,4-Cyclohexadiene has a great

Question 4

Consider the following structure.   This substance could be produced by the reaction of the following diene and dienophile.

Accepted Answer

A) True 
 B)False

Question 5

Consider the reaction below to answer the following question(s):   Enter the appropriate letter in the blank for each the following statements.
-The electrophile in this reaction is ____.

Accepted Answer

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

Question 6

Draw two resonance structures of the reactive intermediate that accounts for the formation of 1,2- and 1,4-addition products upon reaction of 1,3-butadiene with one equivalent of HBr.

Accepted Answer

The answer of Draw two resonance structures of the reactive...

Question 7

When an organic molecule is irradiated with ultraviolet radiation, the energy absorbed by the molecule corresponds to the amount necessary to excite electrons from one molecular orbital to another.

Accepted Answer

A) True 
 B)False

Question 8

Which of the following reaction coordinate diagrams explains the formation of different thermodynamic (T) and kinetic products from the same reactants (R)?

Accepted Answer

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

Question 9

Draw two resonance structures of the reactive intermediate that accounts for the formation of 1,2- and 1,4-addition products upon reaction of 1,3-butadiene with one equivalent of bromine.

Accepted Answer

The answer of Draw two resonance structures of the reactive...

Question 10

Which of the following electronic transitions is (are) apparent in the ultraviolet-visible spectrum of acrolein, H2C=CHCHO?
1)n  $\rarr$ $\pi$*
2)$\pi$  $\rarr$ $\pi$*
3) $\sigma$$\rarr$ $\pi$*

Accepted Answer

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

Question 11

Provide the structures of the constitutional isomers of the two major organic products obtained from the following reaction?

Accepted Answer

The answer of Provide the structures of the constitutional isomers...

Question 12

What is the correct order of exothermicity for hydrogenation of the following hexadienes upon treatment with H2/Pd (more exothermic > less exothermic)?

Accepted Answer

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

Question 13

Which of the following energy diagrams represents the electronic state of the ground state of 1,3-butadiene?

Accepted Answer

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

Question 14

Which of the following laws relates absorbance to the concentration of a sample and the pathlength in ultraviolet-visible spectroscopy?

Accepted Answer

A) Buzz-Beer law 
B) Beer-Lambert law 
C) Duff-Beer law 
D) Christopher-Lambert law 
A) Buzz-Beer law 
B) Beer-Lambert law 
C) Duff-Beer law 
D) Christopher-Lambert law

Question 15

The following two compounds could be easily distinguished by NMR, IR, UV or MS spectra.

Accepted Answer

A) True 
 B)False

Question 16

What are the units of absorbance, A, in ultraviolet-visible spectroscopy?

Accepted Answer

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

Question 17

What is the IUPAC name of the following compound?

Accepted Answer

(E)-2,3-di

Question 18

What quantity is abbreviated as $\varepsilon$ in ultraviolet-visible spectroscopy?

Accepted Answer

A) absorbance 
B) molecular absorptivity 
C) intensity of transmitted light 
D) wavelength of maximum absorbance 
A) absorbance 
B) molecular absorptivity 
C) intensity of transmitted light 
D) wavelength of maximum absorbance

Question 19

The following compound could act as a diene in a Diels-Alder reaction.

Accepted Answer

A) True 
 B)False

Question 20

Which of the following is(are) formed upon addition of 1 mol of Br2 to 1,3-cyclohexane?

Accepted Answer

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

Exam 20: Dienes, Conjugated Systems, and Pericyclic Reactions

What is the systematic IUPAC name of the following compound?

What are the two major organic products obtained from the following reaction?

Which of 1,3-cyclohexadiene and 1,4-cyclohexadiene has the greatest heat of hydrogenation (i.e., the most exothermic reaction with H2 in the presence of a catalyst). Provide a brief explanation for your choice ?

Consider the following structure. This substance could be produced by the reaction of the following diene and dienophile.

Consider the reaction below to answer the following question(s): Enter the appropriate letter in the blank for each the following statements. -The electrophile in this reaction is ____.

Draw two resonance structures of the reactive intermediate that accounts for the formation of 1,2- and 1,4-addition products upon reaction of 1,3-butadiene with one equivalent of HBr.

When an organic molecule is irradiated with ultraviolet radiation, the energy absorbed by the molecule corresponds to the amount necessary to excite electrons from one molecular orbital to another.

Which of the following reaction coordinate diagrams explains the formation of different thermodynamic (T) and kinetic products from the same reactants (R)?

Draw two resonance structures of the reactive intermediate that accounts for the formation of 1,2- and 1,4-addition products upon reaction of 1,3-butadiene with one equivalent of bromine.

Which of the following electronic transitions is (are) apparent in the ultraviolet-visible spectrum of acrolein, H2C=CHCHO? 1)n →\rarr→ π\piπ * 2) π\piπ →\rarr→ π\piπ * 3) σ\sigmaσ→\rarr→ π\piπ *

Provide the structures of the constitutional isomers of the two major organic products obtained from the following reaction?

What is the correct order of exothermicity for hydrogenation of the following hexadienes upon treatment with H2/Pd (more exothermic > less exothermic)?

Which of the following energy diagrams represents the electronic state of the ground state of 1,3-butadiene?

Which of the following laws relates absorbance to the concentration of a sample and the pathlength in ultraviolet-visible spectroscopy?

The following two compounds could be easily distinguished by NMR, IR, UV or MS spectra.

What are the units of absorbance, A, in ultraviolet-visible spectroscopy?

What is the IUPAC name of the following compound?

What quantity is abbreviated as ε\varepsilonε in ultraviolet-visible spectroscopy?

The following compound could act as a diene in a Diels-Alder reaction.

Which of the following is(are) formed upon addition of 1 mol of Br2 to 1,3-cyclohexane?

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

Which of 1,3-cyclohexadiene and 1,4-cyclohexadiene has the greatest heat of hydrogenation (i.e., the most exothermic reaction with H₂ in the presence of a catalyst). Provide a brief explanation for your choice ?

Which of the following electronic transitions is (are) apparent in the ultraviolet-visible spectrum of acrolein, H₂C=CHCHO? 1)n $\rarr$ $\pi$ * 2) $\pi$ $\rarr$ $\pi$ * 3) $\sigma$ $\rarr$ $\pi$ *

What is the correct order of exothermicity for hydrogenation of the following hexadienes upon treatment with H₂/Pd (more exothermic > less exothermic)?

What quantity is abbreviated as $\varepsilon$ in ultraviolet-visible spectroscopy?

Which of the following is(are) formed upon addition of 1 mol of Br₂ to 1,3-cyclohexane?