Question 1

What is the product of the following reaction?

Accepted Answer

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

Question 2

Why is the enolate of acetone less basic than the allyl anion derived from propene?

Accepted Answer

A)  Because there are more atoms in acetone 
B)  Because there are more resonance structures for the enolate of acetone 
C)  It isn't; the allyl anion is less basic. 
D)  One of the resonance structures for the enolate places the negative charge on the more electronegative oxygen. 
A)  Because there are more atoms in acetone 
B)  Because there are more resonance structures for the enolate of acetone 
C)  It isn't; the allyl anion is less basic. 
D)  One of the resonance structures for the enolate places the negative charge on the more electronegative oxygen.

Question 3

Why is it difficult to stop the halogenation of ketones under basic conditions at the mono-halogenated stage?

Accepted Answer

A)  The ketone undergoes a Bayer-Villigar oxidation. 
B)  The ketone is reduced. 
C)  The ketone undergoes an Aldol reaction. 
D)  The bromine helps to stabilize the second enolate, making the product more acidic than the starting material. 
A)  The ketone undergoes a Bayer-Villigar oxidation. 
B)  The ketone is reduced. 
C)  The ketone undergoes an Aldol reaction. 
D)  The bromine helps to stabilize the second enolate, making the product more acidic than the starting material.

Question 4

Which of the following are enol forms of ethyl acetoacetate drawn below?

Accepted Answer

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

Question 5

If you want to form a thermodynamic enolate, you want to:

Accepted Answer

A)  Keep the reaction as cold as possible. 
B)  Use an aprotic solvent such as THF. 
C)  Use a protic solvent such as ethanol. 
D)  Use a carboxylic acid. 
A)  Keep the reaction as cold as possible. 
B)  Use an aprotic solvent such as THF. 
C)  Use a protic solvent such as ethanol. 
D)  Use a carboxylic acid.

Question 6

Which of the following ketones will give a positive iodoform test?

Accepted Answer

A)  3-Heptanone 
B)  2-Pentanone 
C)  3-Hexanone 
D)  Cyclohexanone 
A)  3-Heptanone 
B)  2-Pentanone 
C)  3-Hexanone 
D)  Cyclohexanone

Question 7

What is the product of the following reaction?

Accepted Answer

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

Question 8

Why can't you prepare 2-tert-butylcyclohexanone by the following reaction?

Accepted Answer

A)  Because tert-butyl bromide is too basic. 
B)  Because tert-butyl bromide cannot undergo an SN2 reaction. 
C)  Because tert-butyl bromide is a nucleophile. 
D)  Because tert-butyl bromide is not a stable compound. 
A)  Because tert-butyl bromide is too basic. 
B)  Because tert-butyl bromide cannot undergo an SN2 reaction. 
C)  Because tert-butyl bromide is a nucleophile. 
D)  Because tert-butyl bromide is not a stable compound.

Question 9

Which is the most acidic proton in the following compound?

Accepted Answer

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

Question 10

A simple chemical test to distinguish between acetone and 3-pentanone would be the reaction of the compounds with

Accepted Answer

A)  bromine with acetic acid. 
B)  bromine and aqueous hydroxide ion. 
C)  THF, LDA at -78 °C followed by reaction with bromine. 
D)  base and methyl bromide. 
A)  bromine with acetic acid. 
B)  bromine and aqueous hydroxide ion. 
C)  THF, LDA at -78 °C followed by reaction with bromine. 
D)  base and methyl bromide.

Question 11

Which of the following four compounds is the most acidic?

Accepted Answer

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

Question 12

Which is the more stable form of acetophenone?

Accepted Answer

A)  Only I 
B)  Only II 
C)  Only III 
D)  I and II are equally stable 
A)  Only I 
B)  Only II 
C)  Only III 
D)  I and II are equally stable

Question 13

What is the missing reagent for the following reaction?

Accepted Answer

A)  Br2/HOAc 
B)  Br2/KOH 
C)  Cl2/FeCl3 
D)  Br2/FeBr3 
A)  Br2/HOAc 
B)  Br2/KOH 
C)  Cl2/FeCl3 
D)  Br2/FeBr3

Question 14

Select the appropriate sequence of reactions to accomplish the following synthesis.

Accepted Answer

A)  [1] Br2, CH3CO2H; [2] Li2CO3, LiBr, DMF; [3] CH3CH2CH2CH2Br 
B)  [1] Br2, CH3CO2H; [2] Mg, Et2O; [3] CH3CH2CH2CH2Br 
C)  [1] LDA; [2] BrCH2CH2CH2CH2Br; [3] NaOEt 
D)  [1] NaOEt; [2] BrCH2CH2CH2CH2Br; [3] LDA 
A)  [1] Br2, CH3CO2H; [2] Li2CO3, LiBr, DMF; [3] CH3CH2CH2CH2Br 
B)  [1] Br2, CH3CO2H; [2] Mg, Et2O; [3] CH3CH2CH2CH2Br 
C)  [1] LDA; [2] BrCH2CH2CH2CH2Br; [3] NaOEt 
D)  [1] NaOEt; [2] BrCH2CH2CH2CH2Br; [3] LDA

Question 15

Which is the thermodynamic enolate of 2-methylcyclohexanone?

Accepted Answer

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

Question 16

What is the major product of the following reaction?

Accepted Answer

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

Question 17

What is the starting material required to accomplish the following transformation?

Accepted Answer

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

Question 18

Treatment of 2-hexanone with NaOCH2CH3 followed by CH3Br affords compound X (C7H14O) as the major product. X shows a strong absorption in the IR spectrum at 1713 cm-1, and its 1H NMR data is given below. What is the structure of X?  
$\begin{array}{|l|l|l|l|}
\hline \text { Signal } & \text { Shift } & \text { Multiplicity } & \text { Integration } \
& (\mathbf{p p m}) & \
\hline 1 & 0.96 & \text { triplet } & 3 \mathrm{H} \
\hline 2 & 1.16 & \text { doublet } & 3 \mathrm{H} \
\hline 3 & 1.33 & \text { multiplet } & 2 \mathrm{H} \
\hline 4 & 1.53 & \text { multiplet } & 2 \mathrm{H} \
\hline 5 & 2.09 & \text { singlet } & 3 \mathrm{H} \
\hline 6 & 2.52 & \text { multiplet } & 1 \mathrm{H} \
\hline
\end{array}$

Accepted Answer

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

Question 19

What is (are) the product(s) of the following reaction?

Accepted Answer

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

Question 20

For most compounds with a single keto group in the molecule, equilibrium favors the keto form over the enol form of the compound. This is due largely to what?

Accepted Answer

A)  The C=O bond is much stronger than the C=C bond. 
B)  The C=C bond is much stronger than the C=O bond. 
C)  The keto form can undergo intramolecular hydrogen bonding. 
D)  The enol form can undergo intramolecular hydrogen bonding. 
A)  The C=O bond is much stronger than the C=C bond. 
B)  The C=C bond is much stronger than the C=O bond. 
C)  The keto form can undergo intramolecular hydrogen bonding. 
D)  The enol form can undergo intramolecular hydrogen bonding.

Exam 23: Substitution Reactions of Carbonyl Compounds at the Alpha-Carbon

What is the product of the following reaction?

Why is the enolate of acetone less basic than the allyl anion derived from propene?

Why is it difficult to stop the halogenation of ketones under basic conditions at the mono-halogenated stage?

Which of the following are enol forms of ethyl acetoacetate drawn below?

If you want to form a thermodynamic enolate, you want to:

Which of the following ketones will give a positive iodoform test?

What is the product of the following reaction?

Why can't you prepare 2-tert-butylcyclohexanone by the following reaction?

Which is the most acidic proton in the following compound?

A simple chemical test to distinguish between acetone and 3-pentanone would be the reaction of the compounds with

Which of the following four compounds is the most acidic?

Which is the more stable form of acetophenone?

What is the missing reagent for the following reaction?

Select the appropriate sequence of reactions to accomplish the following synthesis.

Which is the thermodynamic enolate of 2-methylcyclohexanone?

What is the major product of the following reaction?

What is the starting material required to accomplish the following transformation?

What is (are) the product(s) of the following reaction?

For most compounds with a single keto group in the molecule, equilibrium favors the keto form over the enol form of the compound. This is due largely to what?

Structure and Bonding

Acids and Bases

Introduction to Organic Molecules and Functional Groups

Alkanes

Stereochemistry

Understanding Organic Reactions

Alkyl Halides and Nucleophilic Substitution

Alkyl Halides and Elimination Reactions

Alcohols, Ethers and Epoxides

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Alkynes

Oxidation and Reduction

Mass Spectrometry and Infrared Spectroscopy

Nuclear Magnetic Resonance Spectroscopy

Radical Reactions

Conjugation, Resonance, and Dienes

Benzene and Aromatic Compounds

Electrophilic Aromatic Substitution

Carboxylic Acids and the Acidity of the O-H Bond

Introduction to Carbonyl Chemistry; Organometallic Reagents; Oxidation and Reduction

Aldehydes and Ketones Nucleophilic Addition

Carboxylic Acids and Derivatives

Carbonyl Condensation Reactions

Amines

Carbon-Carbon Bond Forming Reactions in Organic Synthesis

Pericyclic Reactions

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