Question 1

1,3-Pentadiene has how many bonding $\pi$ molecular orbitals?

Accepted Answer

A) 1 
B) 2 
C) 3 
D) 4 
E) 0 
A) 1 
B) 2 
C) 3 
D) 4 
E) 0

Question 2

The allyl cation has how many electrons in bonding $\pi$ molecular orbitals?

Accepted Answer

A) 1 
B) 2 
C) 3 
D) 4 
E) 5 
A) 1 
B) 2 
C) 3 
D) 4 
E) 5

Question 3

Which of these conjugated dienes can undergo 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 4

Keeping in mind stereochemistry,how many products are formed by the reaction of one equivalent of HBr with 2-methyl-1,3-cyclohexadiene?

Accepted Answer

A) 2 
B) 4 
C) 6 
D) 8 
E) 10 
A) 2 
B) 4 
C) 6 
D) 8 
E) 10

Question 5

How could the following synthesis be carried out?

Accepted Answer

A) (1)Br2/CCl4; (2)CH3MgCl,ether; (3)CH3ONa/CH3OH 
B) (1)HBr (1 eq); (2)(CH3)2CuLi,ether 
C) (1)HBr (1eq); (2)Li,ether; (3)CuI; (4)CH3Br 
D) More than one of these choices. 
E) All of these choices. 
A) (1)Br2/CCl4; (2)CH3MgCl,ether; (3)CH3ONa/CH3OH 
B) (1)HBr (1 eq); (2)(CH3)2CuLi,ether 
C) (1)HBr (1eq); (2)Li,ether; (3)CuI; (4)CH3Br 
D) More than one of these choices. 
E) All of these choices.

Question 6

How could the following synthesis be carried out?

Accepted Answer

A) (1)Br2/CCl4; (2)CH3CH2MgCl,ether; (3)CH3ONa/CH3OH 
B) (1)HBr,80 S1U1P1$\circ$S1S1P0C; (2)(CH3CH2)2CuLi,ether 
C) (1)HBr,80 S1U1P1$\circ$S1S1P0C; (2)Mg,ether; (3)CH3CH2OH,then H3O+ 
D) More than one of these choices. 
E) All of these choices. 
A) (1)Br2/CCl4; (2)CH3CH2MgCl,ether; (3)CH3ONa/CH3OH 
B) (1)HBr,80 S1U1P1$\circ$S1S1P0C; (2)(CH3CH2)2CuLi,ether 
C) (1)HBr,80 S1U1P1$\circ$S1S1P0C; (2)Mg,ether; (3)CH3CH2OH,then H3O+ 
D) More than one of these choices. 
E) All of these choices.

Question 7

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

Accepted Answer

A) CH3CH=CHCH=CHCH3 
B) CH3CH=CHCH2CH=CH2 
C) CH2=CHCH2CH2CH=CH2 
D) CH2=CHCH(CH3)CH=CH2 
E) CH3CH=C=CHCH2CH3 
A) CH3CH=CHCH=CHCH3 
B) CH3CH=CHCH2CH=CH2 
C) CH2=CHCH2CH2CH=CH2 
D) CH2=CHCH(CH3)CH=CH2 
E) CH3CH=C=CHCH2CH3

Question 8

Which reaction would produce the following compound?

Accepted Answer

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

Question 9

Show the steps and reagents necessary to prepare the following compound from organic compounds having six carbons or less.Use retrosynthetic analysis as a tool to guide your synthesis.

Accepted Answer

The answer of Show the steps and reagents necessary to...

Question 10

Which reaction would produce the following compound?

Accepted Answer

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

Question 11

Which is not a proper resonance structure for 1,3-butadiene?

Accepted Answer

A) CH2=CH-CH=CH2 
B)    
C)    
D)    
E) All of these answer choices are correct. 
A) CH2=CH-CH=CH2 
B)    
C)    
D)    
E) All of these answer choices are correct.

Question 12

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 13

The substituent R on the bicyclic compound shown is considered to be?

Accepted Answer

A) axial 
B) equatorial 
C) endo 
D) exo 
E) Trans 
A) axial 
B) equatorial 
C) endo 
D) exo 
E) Trans

Question 14

Which alkene would you expect to have the lowest heat of hydrogenation?

Accepted Answer

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

Question 15

Which reaction would produce the following compound?

Accepted Answer

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

Question 16

The substituent R on the bicyclic compound shown is considered to be?

Accepted Answer

A) axial 
B) equatorial 
C) endo 
D) exo 
E) trans 
A) axial 
B) equatorial 
C) endo 
D) exo 
E) trans

Question 17

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

Question 18

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

Question 19

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 20

Which compound would have a UV absorption band at longest wavelength?

Accepted Answer

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

Exam 13: Conjugated Unsaturated Systems

1,3-Pentadiene has how many bonding π\piπ molecular orbitals?

The allyl cation has how many electrons in bonding π\piπ molecular orbitals?

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

Keeping in mind stereochemistry,how many products are formed by the reaction of one equivalent of HBr with 2-methyl-1,3-cyclohexadiene?

How could the following synthesis be carried out?

How could the following synthesis be carried out?

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

Which reaction would produce the following compound?

Show the steps and reagents necessary to prepare the following compound from organic compounds having six carbons or less.Use retrosynthetic analysis as a tool to guide your synthesis.

Which reaction would produce the following compound?

Which is not a proper resonance structure for 1,3-butadiene?

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

The substituent R on the bicyclic compound shown is considered to be?

Which alkene would you expect to have the lowest heat of hydrogenation?

Which reaction would produce the following compound?

The substituent R on the bicyclic compound shown is considered to be?

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

Which compound would have a UV absorption band at longest wavelength?

The Basics

Families of Carbon

Acids and Bases

Nomenclature and Conformations of Alkanes and Cycloalkanes

Stereochemistry

Nucleophilic Reactions

Alkenes and Alkynes I

Alkenes and Alkynes II

Nuclear Magnetic Resonance and Mass Spectrometry

Radical Reactions

Alcohols and Ethers

Alcohols From Carbonyl Compounds

Aromatic Compounds

Reactions of Aromatic Compounds

Aldehydes and Ketones

Carboxylic Acids and Their Derivatives

Reactions at the Α Carbon of Carbonyl Compounds

Condensation and Conjugate Addition Reactions of Carbonyl Compounds

Amines

Transition Metal Complexes

Carbohydrates

Lipids

Amino Acids and Proteins

Nucleic Acids and Protein Synthesis

Filters

1,3-Pentadiene has how many bonding $\pi$ molecular orbitals?

The allyl cation has how many electrons in bonding $\pi$ molecular orbitals?