Deck 17: Introduction to Carbonyl Chemistry; Organometallic Reagents; Oxidation and Reduction

Question 1

Which reagent can be used to reduce an acid chloride to an aldehyde?

A)NaBH₄
B)LiAlH(OtBu)₃
C)LiAlH₄
D)FeCl₃

Answer 1

LiAlH(OtBu)₃

Question 2

Why are ketones less reactive than aldehydes?

A)Ketones are more sterically hindered
B)Ketones are less electron deficient due to donation from the two alkyl groups
C)The statement is false; ketones are more reactive than aldehydes
D)Both Ketones are more sterically hindered and Ketones are less electron deficient due to donation from the two alkyl groups

Answer 2

Both Ketones are more sterically hindered and Ketones are less electron deficient due to donation from the two alkyl groups

Question 3

Which reagent can be used to reduce the carbonyl in methyl vinyl ketone?

A)NaBH₄/CH₃OH
B)H₂ and Pd-C
C)FeCl₃
D)NaH

Answer 3

NaBH₄/CH₃OH

Question 4

What is the name of the general reaction type that carboxylic acids,esters,and amides undergo?

A)Electrophilic acyl addition
B)Nucleophilic acyl addition
C)Nucleophilic acyl substitution
D)Electrophilic acyl substitution

Question 5

If a compound is reduced,what is the result?

A)Fewer C-H bonds
B)Increased number of C-H bonds
C)Fewer C-Z bonds
D)Both increased number of C-H bonds and fewer C-Z bonds

Question 6

Why would the alcohol in the following compound need to be protected before reaction?

A)If it isn't protected,the product will be a carboxylic acid.
B)The Grignard reagent will react with the alcohol before the ketone.
C)Magnesium is Lewis acidic and will coordinate with the alcohol.
D)There is no need to protect the alcohol.

Question 7

Which reagent can be used to reduce the alkene in cyclopentenone?

A)NaBH₄
B)LiAlH₄
C)H₂ and Pd-C
D)DIBAL-H

Question 8

What reagent would be used to reduce an amide to an amine?

A)NaBH₄
B)LiAlH(OtBu)₃
C)LiAlH₄
D)FeCl₃

Question 9

What is the name of the general reaction type that aldehydes and ketones undergo?

A)Electrophilic addition
B)Nucleophilic addition
C)Nucleophilic substitution
D)Electrophilic substitution

Question 10

What is the product of the following reaction?

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

Question 11

Rank the following compounds in order of decreasing reactivity in nucleophilic addition reactions,starting with the most reactive compound.

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

Question 12

What is the product of the following reaction?

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

Question 13

What is the product of the following reaction?

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

Question 14

Which of the following terms explain why aldehydes are more reactive than ketones?

A)Electronegativity and resonance
B)Hybridization and resonance
C)Electronegativity and hybridization
D)Sterics and electronics

Question 15

What will be the product of the following reaction (before any aqueous work-up)?

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

Question 16

What is the purpose of a silyl ether?

A)To protect esters from organometallic reagents and other reagents
B)To protect ketones from organometallic reagents and other reagents
C)To protect alcohols from organometallic reagents and other reagents
D)To prevent the formation of carboxylic acids

Question 17

What is the starting material in the following reaction?

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

Question 18

What is the product of the following reaction?

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

Question 19

Rank the following compounds in order of increasing reactivity in nucleophilic acyl substitution reactions,starting with the least reactive compound.

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

Question 20

What are the two steps in a nucleophilic addition mechanism?

A)Nucleophilic attack followed by protonation
B)Nucleophilic attack followed by deprotonation
C)Nucleophilic attack followed by substitution
D)Nucleophilic attack followed by elimination

Question 21

What is the product of the following reaction?

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

Question 22

What is the major organic product of the following reaction?

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

Question 23

What is the major organic product of the following reaction?

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

Question 24

What is the major organic product of the following reaction?

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

Question 25

What reagent can be used to cleave a silyl ether protecting group?

A)NaOMe
B)MeMgBr
C)Bu₄NF
D)Pd/C

Question 26

What is the major organic product in the following sequence of reactions?

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

Question 27

Which of the following statements about organometallic reagents is not true?

A)Organometallic reagents contain a carbon atom bonded to a metal.
B)The more polar the carbon-metal bond,the more reactive the organometallic reagent.
C)Organometallic reagents react as bases and nucleophiles.
D)Organometallic reagents are strong acids that readily donate a proton to water.

Question 28

What carbonyl compound and Grignard reagent could be used to prepare 2-butanol?

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

Question 29

What is the major organic product of the following reaction?

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

Question 30

What is the product of the following reaction?

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

Question 31

What is the major organic product of the following reaction?

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

Question 32

What is the product of the following reaction?

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

Question 33

What is the missing reagent in the reaction below?

A)[1] Mg,[2] CO₂,[3] acidic work-up
B)[1] CO₂,[2] NaOH
C)[1] CO₂,[2] acidic work-up
D)LiAlH₄

Question 34

What is the major organic product of the following reaction?

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

Question 35

What is the major organic product of the following reaction?

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

Question 36

What is the major organic product of the following reaction?

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

Question 37

Rank the carbon-metal bond in the following organometallic reagents in order of decreasing polarity,starting with the most polar.

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

Question 38

What is the major organic product of the following reaction?

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

Question 39

What is the major organic product of the following reaction?

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

Question 40

What is the major organic product in the following sequence of reactions?

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

Question 41

What is the major organic product of the following reaction?

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

Question 42

If the starting material has no stereogenic centers,when carbonyl compounds are reduced with a reagent such as LiAlH₄ or NaBH₄ and a new stereogenic center is formed,what will the composition of the product mixture be?

A)Forms a racemic mixture of the two possible enantiomers
B)Forms more of one enantiomer than another because of steric reactions around the carbonyl
C)Forms more of one enantiomer than another depending on the temperature of the reaction
D)Forms different products depending on the solvent used

Question 43

What is the major organic product of the following reaction?

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

Question 44

What is the missing reagent in the reaction below?

A)PhMgBr then H₂O
B)Benzene,AlCl₃
C)Ph₂CuLi then H₂O
D)PhLi then H₂O

Question 45

The behavior of acid chlorides is different from that of aldehydes in a reaction with a nucleophile because

A)the acid chloride contains a better leaving group
B)the aldehyde is more easily oxidized
C)the carbonyl of the aldehyde is more positive
D)the carbonyl of the aldehyde is less hindered

Question 46

What is the starting material in the reaction below?

A)Bromobenzene
B)Benzyl bromide
C)Benzoic acid
D)Lithium benzoate

Question 47

Both LiAlH₄ and NaBH₄ are reducing agents.Which statement about these reagents is true?

A)Both reagents contain polar metal-hydrogen bonds.The polarity of the B-H bond is greater than the polarity of the Al-H bond,so LiAlH₄ is the stronger reducing agent.
B)Both reagents contain polar metal-hydrogen bonds.The polarity of the B-H bond is greater than the polarity of the Al-H bond,so LiAlH₄ is the weaker reducing agent.
C)Both reagents contain polar metal-hydrogen bonds.The polarity of the B-H bond is less than the polarity of the Al-H bond,so LiAlH₄ is the stronger reducing agent.
D)Both reagents contain polar metal-hydrogen bonds.The polarity of the B-H bond is less than the polarity of the Al-H bond,so LiAlH₄ is the weaker reducing agent.

Question 48

What is the missing reagent in the reaction below?

A)[1] LiAlH₄,[2] H₂O
B)[1] CH₃MgBr (excess),[2] H₂O
C)[1] (CH₃)₂CuLi (excess),[2] H₂O
D)[1] DIBAL-H,[2] H₂O

Question 49

A carbonyl group,C=O,and an alkene,C=C,double bonds are both sp² hybridized.However,the chemistry of these two functional groups is very different.This can be explained by which of the following statements?

A)The bond angle of the carbonyl is larger than the bond angle of the alkene.
B)The electronegative oxygen of the C=O group makes this bond polar.
C)The bond of the C=C is longer that the bond of the C=O.
D)There is more steric crowding in the carbonyl than in the alkene.

Question 50

What is the major product from the following reaction?

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

Question 51

What is the major product from the following reaction?

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

Question 52

What is the major product from the following reaction?

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

Question 53

What is the missing reagent in the reaction below?

A)NaBH₄/CH₃OH
B)H₂,Pd-C
C)LiAlH₄ then H₂O
D)MeMgBr then H₂O

Question 54

What is the major product from the following reaction?

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

Question 55

What is the missing reagent in the reaction below?

A)Et₂CuLi then H₂O
B)EtMgBr then H₂O
C)NaBH₄/CH₃OH
D)H₂,Pd-C

Question 56

Rank the following compounds in order of increasing reactivity toward the nucleophilic hydride reagent,NaBH₄.

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

Question 57

What is the missing reagent in the reaction below?

A)NaBH₄/CH₃OH
B)DIBAL-H
C)H₂,Pd-C
D)LiAlH₄ then H₂O

Question 58

What is the missing reagent in the reaction below?

A)[1] LiAlH₄,[2] H₂O
B)[1] CH₂=CHLi,[2] H₂O
C)[1] (CH₂=CH)₂CuLi,[2] H₂O
D)[1] DIBAL-H,[2] H₂O

Question 59

Rank the following compounds in order of increasing reactivity (least to most reactive)with respect to acyl substitution. I.methyl benzoate
II)benzoylchloride
III)benzamide

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