Deck 18: Ketones and Aldehydes

Question 1

Provide the structure of benzophenone.

Answer 1

PhCOPh

Question 2

Provide the proper IUPAC name for CH₃CHBrCH₂COCH₂CHO.

Answer 2

5-bromo-3-oxohexanal

Question 3

Provide the IUPAC name for (CH₃)₃CCH₂CHClCH₂CHO.

Answer 3

3-chloro-5,5-dimethylhexanal

Question 4

Name the following compound.

Question 5

The positively polarized carbon atom of a carbonyl group acts as ________.

A) an electrophile and a Lewis base
B) a nucleophile and a Lewis base
C) an electrophile and a Lewis acid
D) a nucleophile and a Lewis acid
E) both a Lewis acid and a Lewis base

Question 6

Provide the structure of 4-oxohexanoic acid.

Question 7

Would you expect the carbonyl carbon of benzaldehyde to be more or less electrophilic than that of acetaldehyde? Explain using resonance structures.

Question 8

Name the following compound.

Question 9

Provide the proper IUPAC name for CH₃OCH₂CH₂CH(CH₃)CHO.

Question 10

Provide the proper IUPAC name for CH₃CHOHCH₂COCH₂C(CH₃)₂CH₂CH₃.

Question 11

Which of the following correctly describes the bond angle and hybridizations present in formaldehyde?

A) C, sp²; O, sp³; HCO, ~120°
B) C, sp²; O, sp²; HCO, ~120°
C) C, sp²; O, sp²; HCO, ~109.5°
D) C, sp³; O, sp²; HCO, ~109.5°
E) C, sp³; O, sp³; HCO, ~109.5°

Question 12

Provide the proper IUPAC name for (CH₃)₂CHCH₂CH₂COCH
CH₂.

Question 13

Give an IUPAC name to the following compound. Be sure to include configurational information in the name.

Question 14

Provide the structure of cyclohexanecarbaldehyde.

Question 15

The structure of Taxol, a potent chemotherapeutic, is shown below. In the structure, there are ________ ketones and ________ aldehydes.

A) 1 ketone; 1 aldehyde
B) 1 ketone; 0 aldehydes
C) 6 ketones; 0 aldehydes
D) 5 ketones; 1 aldehyde
E) 0 ketones; 0 aldehydes

Question 16

Provide the IUPAC name for the following compound, including stereochemical designators as appropriate.

Question 17

What is the correct IUPAC name for the following compound?

A) 2-oxocyclohex-3-ene carbaldehyde
B) 5-formylcyclohex-2-enone
C) 2-formylcyclohex-5-enone
D) 3-oxocyclohex-4-enal

Question 18

Provide the IUPAC name for the following compound.

Question 19

Another name for β-methoxybutyraldehyde is ________.

A) 2-methoxypropanal
B) 3-methoxypropanal
C) 2-methoxybutanal
D) 3-methoxybutanal
E) 2-methoxypentanal

Question 20

Provide the proper IUPAC name for PhCH₂CH(CH₃)CH₂CH₂CHO.

Question 21

In the proton NMR spectra of aldehydes and ketones, the protons bonded to carbons adjacent to the carbonyl group typically fall into which of the chemical shift ranges below?

A) 1.0-2.0 ppm
B) 2.0-3.0 ppm
C) 4.0-4.5 ppm
D) 7.0-8.0 ppm
E) 9.0-10.0 ppm

Question 22

Predict the major organic product of the following reaction sequence.

Question 23

Provide the major organic product which results when PhCHOHCH₃ is treated with PCC.

Question 24

In the mass spectrum of 3,3-dimethyl-2-butanone, the base peak will occur at m/z ________.

A) 43
B) 58
C) 84
D) 85
E) 100

Question 25

Which of the following compounds would show only one triplet in its off resonance decoupled spectrum?

A) acetone
B) butanal
C) pentanal
D) 2-pentanone
E) 3-pentanone

Question 26

How might one distinguish an aldehyde from a ketone using IR data alone?

Question 27

In carbon NMR, the carbon atom of the carbonyl group in aldehydes and ketones has a chemical shift of about ________.

A) 20 ppm
B) 40 ppm
C) 60 ppm
D) 120 ppm
E) 200 ppm

Question 28

The strongest absorptions in the UV spectra of aldehydes and ketones are ones which result from ________ electronic transitions.

A) σ to σ^*
B) σ to π^*
C) n to π^*
D) π to π^*
E) π to σ^*

Question 29

Which of the following transitions is usually observed in the UV spectra of ketones?

A) n to π^*
B) n to π
C) σ to n
D) σ to σ^*
E) n to σ^*

Question 30

The proton NMR spectrum of an unknown compound contains a triplet at Which of the following could be this unknown?

A) (CH₃)₃CCHO
B) CH₃CH₂CH₂CO₂H
C) CH₃CH₂CH₂CHO
D) CH₃CO CH₂Ph
E) PhCHO

Question 31

Which of the following compounds is most soluble in water?

A) acetone
B) cyclohexanone
C) 2-butanone
D) 3-octanone
E) benzophenone

Question 32

Name the following compound.

Question 33

Which of the following represents the correct ranking in terms of increasing boiling point?

A) n-butane < 1-butanol < diethyl ether < 2-butanone
B) n-butane < 2-butanone < diethyl ether < 1-butanol
C) 2-butanone < n-butane < diethyl ether < 1-butanol
D) n-butane < diethyl ether < 1-butanol < 2-butanone
E) n-butane < diethyl ether < 2-butanone < 1-butanol

Question 34

Provide the major organic product which results when PhCHO is treated with the following sequence of reagents:

Question 35

When a carbonyl is part of a conjugated π-network, the C O stretch ________.

A) has a higher frequency than in a nonconjugated system
B) has a lower frequency than in a nonconjugated system
C) always occurs at 1710 cm^-1
D) occurs around 2700 cm^-1
E) cannot be distinguished from the C O stretch in a nonconjugated system

Question 36

Which is more soluble in water, 2-butanone or n-hexane? Explain.

Question 37

How would you perform the following transformation?

A) NaBH₄
B) LiAlH₄
C) 1. DIBAL-H 2. H₂O
D) 1. SOCl₂ 2. LiAlH(O-t-Bu)₃

Question 38

What reagent can be used to convert 2-methylbutan-1-ol into 2-methylbutanal?

A) LiAlH₄
B) Na₂Cr₂O₇
C) O₃
D) KMnO₄
E) PCC

Question 39

What reagents can be used to convert 1-hexyne into 2-hexanone?

A) 1. Sia₂BH; 2. H₂O₂, NaOH
B) Hg²⁺, H₂SO₄, H₂O
C) 1. O₃; 2. (CH₃)₂S
D) 1. CH₃MgBr; 2. CO₂
E) 1. H₂, Ni; 2. Na₂Cr₂O₇, H₂SO₄

Question 40

Which compound will show an intense peak in the mass spectrum at m/z 58?

A) CH₃COCH₂CH₂CH₃
B) (CH₃)₂CHCOCH₃
C) CH₃CH₂COCH₂CH₃
D) (CH₃)₃CCHO
E) (CH₃)₃CCOCH₃

Question 41

Which series of reactions described below, if any, will result in the formation of 2-methylpentan-3-one starting with 1-propanol?

A) 1. (CH₃)₂CHMgBr/ diethyl ether
2) dilute H₃O⁺
3) PCC
B) 1. Na₂Cr₂O₇/H₂SO₄ and heat
2) SOCl₂
3) 2 (CH₃)₂CHMgBr/ diethyl ether
4) H₃O⁺
C) 1. Na₂Cr₂O₇/H₂SO₄ and heat
2) (CH₃)₂CHMgBr/ diethyl ether
3) dilute H₃O⁺
4) LiAlH₄
D) 1. PCC
2) (CH₃)₂CHLi/ diethyl ether
3) dilute H₃O⁺
4) Na₂Cr₂O₇/H₂SO₄ and heat
E) none of the above

Question 42

Beginning with sodium acetylide (NaCCH), propose a three-step synthesis of hexanal.

Question 43

Which of the following describes a synthesis of an aldehyde?

A) hydrogenation of an acid chloride using Pd/BaSO₄/S as a poisoned catalyst
B) reaction of a primary alcohol with Na₂Cr₂O₇
C) reaction of a ketone with ozone
D) treatment of an alkene with Sia₂BH
E) none of the above

Question 44

Provide the major organic product which results when
is treated with excess butyllithium followed by H₃O⁺.

Question 45

Complete the following reaction by filling in the necessary reagents.

Question 46

Show how you would perform the following synthesis.

A) 1. O₃ 2. (CH₃)₂S
B) KMnO₄, cold, basic
C) OsO₄
D) 1. mCPBA 2. potassium dichromate

Question 47

Name the compound generated when ethylbenzene is treated with CO, HCl, AlCl₃, and CuCl.

Question 48

Oxidation of a 1° alcohol with pyridinium chlorochromate results in the production of ________.

A) an ester
B) a ketone
C) an aldehyde
D) an ether
E) none of the above

Question 49

Provide the major organic product of the reaction shown below.

Question 50

Provide the major organic product which results when pentanal is subjected to the following sequence of steps:

Question 51

Oxidation of a 2° alcohol with chromic acid results in the production of ________.

A) an ester
B) a ketone
C) an aldehyde
D) an ether
E) none of the above

Question 52

Provide the major organic product of the reaction shown below.

Question 53

By which single reaction can benzene be readily converted into acetophenone?

Question 54

Provide the reagents to perform the following synthesis.

Question 55

Treatment of a nitrile with a Grignard reagent followed by hydrolysis results in ________.

A) an ester
B) a ketone
C) an aldehyde
D) an ether
E) an alcohol

Question 56

Propose a synthesis of 3-heptanone from propanal.

Question 57

Oxidation of a 3° alcohol with chromic acid results in the production of ________.

A) an ester
B) a ketone
C) an aldehyde
D) an ether
E) none of the above

Question 58

Which of the following reactions will not yield a ketone product?

A)
B)
C)
D)
E)

Question 59

Show how you would perform the following synthesis.

Question 60

How might one prepare 4-heptanone from CH₃CH₂CH₂CN in two steps?

Question 61

Provide the structure of the hydrate of cyclopentanone.

Question 62

What organic compound is generated when PhCOCl is treated with

Question 63

When the carbonyl group of a neutral ketone is protonated ________.

A) the resulting species becomes more electrophilic
B) the resulting species is activated toward nucleophilic attack
C) subsequent nucleophilic attack on the resulting species is said to occur under acid-catalyzed conditions
D) the resulting species has a positive charge
E) all of the above

Question 64

Provide the major organic product of the reaction shown below.

Question 65

Provide the major organic product of the reaction shown below.

Question 66

Provide the major organic product of the reaction shown below.

Question 67

Provide the single reagent necessary for the conversion of cyclobutanone to the compound shown below.

Question 68

An ylide is a molecule that can be described as a ________.

A) carbanion bound to a negatively charged heteroatom
B) carbocation bound to a positively charged heteroatom
C) carbocation bound to a carbon radical
D) carbocation bound to a diazonium ion
E) carbanion bound to a positively charged heteroatom

Question 69

Propose a synthesis of 4-phenylbutan-2-ol from 3-phenylpropanal.

Question 70

Propose a synthesis of 3-methylhept-4-yn-3-ol from but-1-yne.

Question 71

Provide a detailed, stepwise mechanism for the base-catalyzed hydration of 2-butanone.

Question 72

Provide the major organic product which results when
is treated with

Question 73

The following compound has been found effective in treating pain and inflammation (J. Med. Chem. 2007, 4222). Which sequence correctly ranks each carbonyl group in order of increasing reactivity toward nucleophilic addition?

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

Question 74

Which sequence ranks the following carbonyl compounds in order of increasing rate of nucleophilic addition?

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

Question 75

Why are the equilibrium constants for hydration of aldehydes typically greater than those of ketones?

Question 76

Consider the equilibrium of each of the carbonyl compounds with HCN to produce cyanohydrins. Which is the correct ranking of compounds in order of increasing K_eq for this equilibrium?

A) H₂CO < cyclohexanone < CH₃CHO < 2-methylcyclohexanone
B) CH₃CHO < 2-methylcyclohexanone < cyclohexanone < H₂CO
C) cyclohexanone < 2-methylcyclohexanone < H₂CO < CH₃CHO
D) cyclohexanone < 2-methylcyclohexanone < CH₃CHO < H₂CO
E) 2-methylcyclohexanone < cyclohexanone < CH₃CHO < H₂CO

Question 77

Draw two major resonance forms of the cation which results when cyclohexanone's carbonyl group is protonated.

Question 78

Rank the following compounds in order of their propensity to become a hydrate in water (i.e., start with the least easy to hydrate: CH₃COCH₂CH₃, H₂CO, Cl₃CCHO, and CH₃CH₂CHO.

Question 79

What reagent can be used to convert benzophenone into triphenylmethanol?

Question 80

Through what sequence of steps can toluene be converted into