Deck 22: Alpha Carbon Chemistry: Enols and Enolates

Question 1

Predict the major product for the following reaction.

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

Answer 1

I

Question 2

Which of the following base will completely convert 1,4-cyclohexanedione into an enolate?

A)sodium hydroxide
B)sodium ethoxide
C)LDA
D)sodium hydride
E)both C & D

Answer 2

both C & D

Question 3

Provide the structure of the enolate when acetophenone is treated with strong base.

Answer 3

Question 4

Which are the most acidic $\alpha$ - hydrogens in the following compounds?

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

Question 5

Provide the structure of the enol when 3,3,6-trimethyl-4-heptanone is treated with acid.

Question 6

Which is the most acidic hydrogen in the following compound?

A)I
B)II
C)III
D)IV
E)all of these

Question 7

Which is the most acidic hydrogen in the following compound?

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

Question 8

Which of the following compound(s)would undergo racemization in presence of a base?

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

Question 9

Explain why the following equilibrium favors the enol tautomer.

Question 10

Which one of the following compounds would undergo racemization at the $\alpha$ -stereocenter in presence of a base?

A)I
B)II
C)III
D)IV
E)none of these

Question 11

Which one of the following is the most acidic compound?

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

Question 12

Which one of the following compound does not undergo an aldol addition reaction in presence of aqueous sodium hydroxide?

A)butanal
B)2-methylbutanal
C)3-methylpentanal
D)2,2-dimethylbutanal
E)none of these

Question 13

Predict the major product for the following reaction.

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

Question 14

Which of the following is(are)a keto-enol tautomeric pair(s)?

A)I
B)II
C)III
D)I & II
E)I & III

Question 15

Which of the following is (are)a keto-enol tautomeric pair(s)?

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

Question 16

Which one of the following compounds is most acidic?

A)ethyl acetoacetate
B)2-butanone
C)ethyl pentanoate
D)1-butanol
E)3-pentanone

Question 17

Which one of the following compounds would favor the enol tautomer over the ketone tautomer?

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

Question 18

Explain why the following equilibrium favors the enol tautomer.

Question 19

Predict the major product for the following reaction.

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

Question 20

Provide the reactant that would yield m-chlorobenzoic acid using the haloform reaction.

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

Question 21

Which one of the following is a major product in a Claisen condensation?

A) $\infty$ -keto ester
B) $\beta$ -keto ester
C) $\beta$ -hydroxy ester
D) $\gamma$ -hydroxyester
E) $\beta$ -diketone

Question 22

Predict the major product for the following reaction.

A)I
B)II
C)III
D)IV
E)none of these

Question 23

Provide the reactant(s)that would give the following aldol condensation product.

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

Question 24

Predict the product when cyclohexanone reacts with aqueous sodium hydroxide at 100⁰C.

A)I
B)II
C)III
D)IV
E)none of these

Question 25

Predict the major product for the following reaction.

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

Question 26

Predict the major product for the following reaction.

A)I
B)II
C)III
D)IV
E)none of these

Question 27

Provide the reactant(s)that would give the following possible aldol condensation product.

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

Question 28

Predict the major product for the following reaction.

Question 29

Provide the reactant(s)that would give the following aldol condensation product.

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

Question 30

Predict the major product for the following reaction.

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

Question 31

Predict the major product for the following reaction.

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

Question 32

Explain why CH₃ONa should not be used for Claisen condensation of ethylbutanoate.

Question 33

Predict the product for the following reaction.

A)I
B)II
C)III
D)IV
E)none of these

Question 34

Provide the reactants that would give the following aldol condensation product.

Question 35

Predict the product for the following reaction.

A)I
B)II
C)III
D)IV
E)none of these

Question 36

Predict the product for the following reaction.

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

Question 37

Provide the reactants that would give the following aldol condensation product.

A)I
B)II
C)III
D)IV
E)none of these

Question 38

Which one of the following is not a possible product when a crossed aldol addition reaction is carried out with ethanal and butanal as reactants?

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

Question 39

Provide the reactants that would give the following aldol condensation product.

A)I
B)II
C)III
D)IV
E)none of these

Question 40

Predict the major product for the following reaction.

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

Question 41

Predict the product(s)for the following reaction.

A).I
B).II
C).III
D).IV
E)All of these

Question 42

Predict the major product for the following reaction sequence.

Question 43

Predict the product for the following Dieckmann-like cyclization.

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

Question 44

Provide the reactant(s)that will yield the following Claisen condensation product.

Question 45

Predict the product(s)for the following reaction.

A) I
B) II
C) III
D) IV
E)none of these

Question 46

Provide the reactants that will yield the following compound as crossed Claisen condensation product.

Question 47

Predict the product(s)for the following reaction.

A) I
B) II
C) III
D) IV
E)none of these

Question 48

Provide the structure of reactant (X)for the following reaction.

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

Question 49

Predict the final product for the following reaction sequence.

A)2-methylheptanoic acid
B)3-methylhexanoic acid
C)3-methylpentanoic acid
D)2-methylpentanoic acid
E)ethyl 2-methylheptanoate

Question 50

Predict the product(s)for the following reaction sequence.

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

Question 51

Which of the following compounds can be prepared using the Dieckmann condensation

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

Question 52

Predict the product(s)for the following reaction.

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

Question 53

Predict the product(s)for the following reaction.

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

Question 54

Predict the product(s)for the following reaction.

A) I
B) II
C) III
D) IV
E)none of these

Question 55

Provide a stepwise synthesis for the following compound starting with cycloheptene and using the Dieckmann cyclization.

Question 56

Predict the product(s)for the following reaction sequence.

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

Question 57

Predict the product(s)for the following reaction.

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

Question 58

Predict the product(s)for the following reaction.

A) I
B) II
C) III
D) IV
E)all of these

Question 59

Explain if the following reaction will yield the product shown.

Question 60

Predict the product(s)for the following reaction.

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

Question 61

Which of the following ketones cannot be prepared using acetoacetic ester synthesis?

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

Question 62

Predict the product for the following reaction.

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

Question 63

Predict the product for the following reaction sequence.

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

Question 64

Predict the product for the following reaction.

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

Question 65

Predict the product for the following reaction sequence.

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

Question 66

Predict the product(s)for the following reaction sequence.

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

Question 67

Predict the final product for the following reaction sequence.

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

Question 68

Which of the following amines will form an enamine with aldehydes and ketones?

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

Question 69

Provide the structures of the intermediates and the final product in the following reaction sequence.

Question 70

Predict the product for the following reaction.

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

Question 71

Predict the product for the following reaction sequence.

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

Question 72

Which one of the following nucleophiles will undergo conjugate addition in Michael reaction?

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

Question 73

Which one of the following is the most reactive Michael acceptor?

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

Question 74

Predict the final product for the following reaction sequence.

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

Question 75

Which one of the following compounds can be prepared using the Michael reaction?

A)I
B)II
C)III
D)IV
E)none of these

Question 76

Provide the reagents necessary to carry out the following conversion.

A)
B)
C)
D)
E)all of these

Question 77

Predict the product for the following reaction sequence.

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

Question 78

Predict the product for the following reaction.

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

Question 79

Predict the product for the following reaction.

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

Question 80

Which of the following amines will form an enamine with aldehydes and ketones?

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