Deck 10: Alkenes

Question 1

What is the IUPAC name for the following compound?

A)4-Ethyl-3-methyl-1-octen-5-ol
B)3-Ethyl-4-methyl-2-octen-5-ol
C)5-Ethyl-6-methyl-7-octen-4-ol
D)4-Ethyl-6-methyl-1-octen-5-ol

Answer 1

5-Ethyl-6-methyl-7-octen-4-ol

Question 2

What is the IUPAC name for the following compound?

A)1-Methylcyclopentene
B)2-Methyl-1-cyclopentene
C)1-Methylene-1-methylcyclopentane
D)1-Methylcyclohexene

Answer 2

1-Methylcyclopentene

Question 3

Which of the following is a terpene?

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

Answer 3

IV

Question 4

In which of the following alkene addition reactions will carbocation rearrangements occur?

A)Addition of Br₂ and H₂O
B)Addition of Br₂
C)Addition of Cl₂ and H₂O
D)Addition of H₂O in the presence of H₂SO₄

Question 5

Rank the following compounds in order of decreasing stability, putting the most stable first.

A)I > II > III
B)II > I > III
C)III > II > I
D)III > I > II

Question 6

Which of the following alkenes are terminal alkenes?

A)I and II
B)II and III
C)I and IV
D)I and III

Question 7

Which of the statements about the properties of the carbon-carbon double bond is not true?

A)There is restricted rotation around the carbon-carbon double bond.
B)Whenever the two groups on each end of a carbon-carbon double bond are the same, two diastereomers are possible.
C)Trans alkenes are generally more stable than cis alkenes.
D)The stability of the carbon-carbon double bond increases as the number of substituent groups increases.

Question 8

What is the common name of the following compound?

A)2-Vinylcyclohexene
B)2-Allylcyclohexene
C)1-Allylcyclohexene
D)1-Vinylcyclohexene

Question 9

Which of the following reaction conditions would result in anti-Markovnikov addition to an alkene?

A)H₂O/H₃O⁺
B)HBr
C)HCl
D)[1] BH₃; [2] H₂O₂/HO^-

Question 10

Which of the following compounds has the highest boiling point?

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

Question 11

Markovnikov addition of HBr to CH₃CH=CH₂ involves which of the following?

A)Initial attack by bromide anion (Br^-).
B)Initial attack by bromine radical (Br•).
C)Formation of a primary carbocation.
D)Formation of a secondary carbocation.

Question 12

Calculate the degree of unsaturation for a molecule with molecular formula C₆H₁₁Cl.

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

Question 13

Rank the following isomers in order of increasing boiling point, putting the least first.

A)I < II < III
B)I < III < II
C)II < III < I
D)II < I < III

Question 14

Which of the following statements about alkenes is not true?

A)They are less reactive than alkanes.
B)They can exist as cis/trans isomers.
C)The bond angle around the C-C double bond is approximately 120°.
D)The carbon of the C-C double bond is sp² hybridized.

Question 15

What is the major product of the following reaction?

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

Question 16

Calculate the degree of unsaturation for a molecule with molecular formula C₈H₉N.

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

Question 17

Rearrangements can occur in which of the following reactions?

A)Addition of Cl₂ to an alkene.
B)Addition of HOBr to an alkene.
C)Addition of H₂O/H₃O⁺ to an alkene.
D)None of these.

Question 18

Which of the following statements about alkenes is true?

A)Alkenes react with nucleophiles and bases.
B)Alkenes contain double bonds from two sp-hybridized carbon atoms.
C)In the reactions of alkenes, the always broken.
D)Alkenes react with electrophiles.

Question 19

Which of the following alkenes will undergo a carbocation rearrangement when reacting with H₂O in the presence of a small amount of H₂SO₄?

A)Only I and II
B)Only I and III
C)Only II and III
D)I, II, and III

Question 20

Which of the following alkenes reacts fastest with HCl?

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

Question 21

What is the starting material in the following reaction?

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

Question 22

What is (are) the major product(s) obtained from the following reaction?

A)Only I
B)Only II
C)Only III
D)Only I and II

Question 23

Predict the major product of the following reaction.

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

Question 24

What is the best choice of reagent to accomplish the following transformation?

A)H₂O, Br₂
B)[1] BH₃; [2] H₂O₂/HO^-
C)H₂O, H₂SO₄
D)[1] BH₃; [2] H₂O

Question 25

Predict the product of the following reaction.

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

Question 26

Predict the major product of the following reaction.

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

Question 27

Rank the carbocation in order of increasing stability, putting the least stable first.

A)III < I < II
B)III < II < I
C)I < II < III
D)I < III < II

Question 28

What type of reactive intermediate is formed in the reaction of an alkene with HI to give an iodoalkane?

A)Carbanion
B)Carbocation
C)Cyclic bromonium ion
D)Radical

Question 29

Predict the major product(s) of the following reaction.

A)Only I and II
B)Only II and IV
C)Only II and III
D)Only I and IV

Question 30

Which of the following statements about the stereochemistry of electrophilic addition of HX to alkenes is true?

A)Achiral starting materials yield an unequal mixture of two enantiomers.
B)Hydrohalogenation occurs with syn stereochemistry only.
C)Hydrohalogenation occurs with anti stereochemistry only.
D)Hydrohalogenation occurs with syn and anti addition of HX.

Question 31

Predict the product of the following reaction, ignoring stereochemistry.

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

Question 32

What is (are) the missing reagent(s) in the following reaction?

A)Br₂/CCl₄
B)NBS, DMSO/H₂O
C)[1] Br₂; [2] H₂O
D)[1] BH₃; [2] H₂O₂/HO^-

Question 33

What is (are) the major product(s) obtained from the following reaction?

A)Only I
B)Only II
C)Only III
D)Only I and II

Question 34

Which of the following reactions of alkenes takes place with anti stereochemistry only?

A)Addition of HBr
B)Addition of H₂O in the presence of H₂SO₄
C)Addition of BH₃ followed by H₂O₂/HO^-
D)Addition of Br₂

Question 35

Predict the major product(s) of the following reaction.

A)Only I and II
B)Only II and III
C)Only III and IV
D)Only I and IV

Question 36

What is the major product obtained from the following reaction (assume enantiomer is also formed)?

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

Question 37

Predict the product(s) of the following reaction.

A)Only I and II
B)Only I and III
C)Only II and III
D)Only III and IV

Question 38

Predict the major product of the following reaction.

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

Question 39

What type of reactive intermediate is formed in the reaction of an alkene with Br₂ and H₂O to give a bromohydrin?

A)Carbanion
B)Radical
C)Carbocation
D)Cyclic bromonium ion

Question 40

What is the best choice of reagent to accomplish the following transformation?

A)HBr
B)Br₂, H₂O
C)Br₂
D)H₂O₂/Br₂

Question 41

Which alkene reacts fastest with HBr?

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

Question 42

Which of the following alkenes is an E alkene?

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

Question 43

Which of the following statements about hydroboration/oxidation of alkenes is true?

A)In hydroboration, the boron atom bonds to the more substituted carbon.
B)Hydroboration occurs with anti addition.
C)Oxidation occurs with retention of configuration.
D)9-BBN does not undergo hydroboration in the same manner as BH₃.