Deck 8: Reactions of Alkenes

Question 1

Draw the major organic product generated in the reaction below. Pay particular attention to regio- and stereochemical detail.

Answer 1

Question 2

Draw the major regioisomeric product generated in the reaction below.

Answer 2

Question 3

Draw the major organic product generated in the reaction below. Pay particular attention to regio- and stereochemical detail.

Answer 3

Question 4

Predict the major product of the following reaction.

A)

B)

C)

D)

Question 5

Draw the major organic product generated in the reaction below. Pay particular attention to regio- and stereochemical detail.

Question 6

HBr can be added to an alkene in the presence of peroxides (ROOR). What function does the peroxide serve in this reaction?

A) nucleophile
B) electrophile
C) radical chain initiator
D) acid catalyst
E) solvent

Question 7

Explain the regioselectivity observed in the radical addition of HBr to 2-methylpropene.

Question 8

When propylene reacts with hydrogen bromide in the presence of a peroxide initiator, which of the following structures are formed during the mechanism?

A)
B)
C)
D) H∙

Question 9

Provide the structure of the major organic product of the reaction below.

Question 10

Provide the major organic product of the reaction below.

Question 11

Provide the structure of the major organic product of the reaction below.

Question 12

Draw the major organic product generated in the reaction below. Pay particular attention to regio- and stereochemical detail.

Question 13

Name the major product which results when HBr is added to 3-ethyl-3-hexene.

Question 14

Provide the structure of the major organic product of the reaction below.

Question 15

Draw the major organic product generated in the reaction below. Pay particular attention to regio- and stereochemical detail.

Question 16

Draw the major organic product generated in the reaction below. Pay particular attention to regio- and stereochemical detail.

Question 17

Draw the major organic product generated in the reaction below. Pay particular attention to regio- and stereochemical detail.

Question 18

Complete the following reaction and provide a detailed, step-by-step mechanism for the process.

Question 19

Draw the major organic product generated in the reaction below. Pay particular attention to regio- and stereochemical detail.

Question 20

Based on the relative stabilities of the intermediates involved, explain the basis for Markovinkov's rule in the addition of hydrogen halides to alkenes.

Question 21

Which of the following intermediates is thought to occur in the mechanism by which alkenes are hydrated in the presence of acid?

A) carbanion
B) carbocation
C) free radical
D) carbene
E) alkyne

Question 22

Draw the major organic product generated in the reaction below. Pay particular attention to regio- and stereochemical detail.

Question 23

Draw the major organic product generated in the reaction below. Pay particular attention to regio- and stereochemical detail.

Question 24

Provide the reagents necessary to complete the following transformation.

A) 1. BH₃^∙THF 2. H₂O₂, HO^-
B) H₂O, H₂SO₄
C) OsO₄, H₂O₂
D) CH₃CO₃H
E) 1. CH₃CO₃H 2. H⁺, H₂O

Question 25

Name the major alcohol product which results when 3,3-dimethylbut-1-ene is treated with dilute acid.

Question 26

The following reaction is known to proceed by a free radical chain mechanism. Suggest a reasonable, step-by-step mechanism for this reaction.
CH₃CH-CH₂ + CHCl₃ CH₃CH₂CH₂CCl₃

Question 27

Draw the major organic product generated in the reaction below. Pay particular attention to regio- and stereochemical detail.

Question 28

Draw the major organic product(s) generated in the reaction below. Pay particular attention to regio- and stereochemical detail.

Question 29

Provide the reagents necessary to complete the following transformation.

Question 30

When 3,6-dimethylcyclohexene is reacted with dry gaseous HBr, one of the products is 1-bromo-1,4-dimethylcyclohexane. Provide a detailed step-by-step mechanism to explain the formation of this product

Question 31

Draw the major organic product generated in the reaction below. Pay particular attention to regio- and stereochemical detail.

Question 32

Draw the major organic product generated in the reaction below. Pay particular attention to regio- and stereochemical detail.

Question 33

Provide the structure of the major organic product of the reaction below.

Question 34

Acid catalyzed hydration (H₂SO₄/water/△) of an unknown compound (A)with a chemical formula C₆H₁₂, yielded a racemic mixture of product C₆H₁₃OH. Which, if any, of the following compounds is/are possible structures for the initial compound (A)?

A) compound 1 only
B) compounds 2 and 3
C) compound 2 only
D) compounds 1 and 3
E) none of the above

Question 35

The mechanism for the acid-catalyzed hydration of alkenes is simply the reverse of the mechanism by which alcohols are dehydrated using concentrated acid. This is an illustration of the principle of ________.

Question 36

What synthetic goal is achieved by subjecting an alkene to an oxymercuration-demercuration sequence?

A) Markovnikov addition of H₂O wherein skeletal rearrangement is promoted
B) Markovnikov addition of H₂O wherein skeletal rearrangement is prevented
C) anti-Markovnikov addition of H₂O wherein skeletal rearrangement is promoted
D) anti-Markovnikov addition of H₂O wherein skeletal rearrangement is prevented
E) syn-hydroxylation

Question 37

What is the major product of the following reaction?

A)

B)

C)

D)

Question 38

Draw the major organic product generated in the reaction below. Pay particular attention to regio- and stereochemical detail.

Question 39

Complete the following reaction and provide a detailed, step-by-step mechanism for the process.

Question 40

Which of the following is the best reaction sequence to use if one wants to accomplish a Markovnikov addition of water to an alkene with minimal skeletal rearrangement?

A) water + dilute acid
B) water + concentrated acid
C) oxymercuration-demercuration
D) hydroboration-oxidation
E) none of the above

Question 41

Treatment of 2-methylpropene with which of the following reaction conditions results in an anti-Markovnikov addition product?

A) dry gaseous HBr with peroxides present
B) BH₃-THF, followed by alkaline H₂O₂
C) aqueous Hg(OAc)₂, followed by alkaline NaBH₄
D) dilute H₂SO₄ and heat
E) both A and B

Question 42

Provide the structure of the major organic product of the reaction below.

Question 43

Draw the major organic product generated in the reaction below. Pay particular attention to regio- and stereochemical detail.
(Z)-3-hexene →

Question 44

Provide the structure of the major organic product of the reaction below.

Question 45

Draw the major organic product generated in the reaction below. Pay particular attention to regio- and stereochemical detail.

Question 46

Draw the major organic product generated in the reaction below. Pay particular attention to regio- and stereochemical detail.

Question 47

Draw the major organic product generated in the reaction below. Pay particular attention to regio- and stereochemical detail.

Question 48

Draw a structure for the $\textbf{ transition state }$ of the following reaction. Include correct partial charges.

Question 49

Draw the major organic product generated in the reaction below. Pay particular attention to regio- and stereochemical detail.

Question 50

Both (E)- and (Z)-hex-3-ene can be subjected to a hydroboration-oxidation sequence. How are the products from these two reactions related to each other?

A) The (E)- and (Z)-isomers generate the same products but in differing amounts.
B) The (E)- and (Z)-isomers generate the same products in exactly the same amounts.
C) The products of the two isomers are related as constitutional isomers.
D) The products of the two isomers are related as diastereomers.
E) The products of the two isomers are not structurally related.

Question 51

Draw the major organic product generated in the reaction below. Pay particular attention to regio- and stereochemical detail.

Question 52

Draw the major organic product generated in the reaction below. Pay particular attention to regio- and stereochemical detail.

Question 53

Draw the major organic product generated in the reaction below. Pay particular attention to regio- and stereochemical detail.

Question 54

When an alkene is subjected to treatment with Hg(OAc)₂ in alcohol followed by reaction with NaBH₄, what new class of compound is formed?

A) ether
B) epoxide
C) alkane
D) syn diol
E) alkyne

Question 55

Provide the reagents necessary to complete the following transformation.

A) 1. BH₃^∙THF   2. H₂O₂, HO^-
B) H₂O, H₂SO₄
C) OsO₄, H₂O₂
D) CH₃CO₃H
E) 1. CH₃CO₃H   2. H⁺, H₂O

Question 56

Draw the major organic product generated in the reaction below. Pay particular attention to regio- and stereochemical detail.

Question 57

Provide the structure of the major organic product of the reaction below.

Question 58

Provide the reagents necessary to convert 3-methyl-2-butanol to 2-methyl-2-butanol.

Question 59

Complete the following reaction by filling in the appropriate reagents.

Question 60

Provide the structure of the major organic product of the reaction below.

Question 61

Complete the following reaction and provide a detailed, step-by-step mechanism for the process.

Question 62

Both (E)- and (Z)-hex-3-ene can be treated with D₂ in the presence of a platinum catalyst. How are the products from these two reactions related to each other?

A) The (E)- and (Z)-isomers generate the same products but in differing amounts.
B) The (E)- and (Z)-isomers generate the same products in exactly the same amounts.
C) The products of the two isomers are related as constitutional isomers.
D) The products of the two isomers are related as diastereomers.
E) The products of the two isomers are related as enantiomers.

Question 63

Addition of Br₂ to (E)-hex-3-ene produces ________.

A) a meso dibromide
B) a mixture of enantiomeric dibromides which is optically active
C) a mixture of enantiomeric dibromides which is optically inactive
D) (Z)-3,4-dibromo-3-hexene
E) (E)-3,4-dibromo-3-hexene

Question 64

Draw the major organic product generated in the reaction below. Pay particular attention to regio- and stereochemical detail.

Question 65

Draw the major organic product(s) generated in the reaction below. Pay particular attention to regio- and stereochemical detail.

Question 66

Consider how the I-Cl bond is polarized and predict the product which results when this mixed halogen adds to 1-methylcyclohexene.

Question 67

________ is the use of an optically active reagent or catalyst to convert an optically inactive starting material into an optically active product.

A) Asymmetric induction
B) Racemization
C) Optical reduction
D) Meso effection
E) Chiralization

Question 68

Draw the major organic product generated in the reaction below. Pay particular attention to regio- and stereochemical detail.

Question 69

Which of the following alkenes will yield a meso dihalide when reacted with Br₂/CCl₄ at room temperature?

A)

B)

C)

D)

E) both Band D

Question 70

Which of the following additions to alkenes occur(s) specifically in an anti fashion?

A) hydroboration-oxidation
B) addition of Br₂
C) addition of H₂
D) addition of H₂O in dilute acid
E) both A and B

Question 71

Draw the major organic product generated in the reaction below. Pay particular attention to regio- and stereochemical detail.

Question 72

Draw the major organic product generated in the reaction below. Pay particular attention to regio- and stereochemical detail.

Question 73

Draw the major organic product generated in the reaction below. Pay particular attention to regio- and stereochemical detail.

Question 74

Complete the following reaction by providing a structure of the expected product. Be sure to indicate all relevant stereochemistry.

Question 75

Humulene is a monocyclic terpene constituent of carnations. When 0.25 mol of humulene is hydrogenated in the presence of platinum catalyst, 0.75 mol of H₂ reacts with the humulene to produce a monocyclic hydrocarbon of formula C₁₅H₃₀. What is the molecular formula of humulene?

Question 76

Provide the major organic product of the reaction below.

Question 77

Draw the major organic product generated in the reaction below. Pay particular attention to regio- and stereochemical detail.

Question 78

Provide a detailed, step-by-step mechanism for the reaction shown below.

Question 79

Predict the product of the following reaction. Include any relevant stereochemistry.

Question 80

Provide the structure of the major organic product of the reaction below.