Question 1

In an acid-catalyzed hydration, which of the following alkynes is expected to produce a single ketone?

Accepted Answer

A)  2-decyne 
B)  3-decyne 
C)  4-decyne 
D)  5-decyne 
E)  All of the above will give a single product 
A)  2-decyne 
B)  3-decyne 
C)  4-decyne 
D)  5-decyne 
E)  All of the above will give a single product

Question 2

Provide the IUPAC name for the alkyne expected to produce the two compounds listed below upon ozonolysis. CH3CH2CO2H and (CH3)3CCO2H

Accepted Answer

A)  1-tert-butyl-1-butyne 
B)  2,2-dimethyl-3-hexyne 
C)  3,3-dimethyl-2-hexyne 
D)  5,5-dimethyl-3-hexyne 
E)  3-octyne 
A)  1-tert-butyl-1-butyne 
B)  2,2-dimethyl-3-hexyne 
C)  3,3-dimethyl-2-hexyne 
D)  5,5-dimethyl-3-hexyne 
E)  3-octyne

Question 3

What is the final major product expected for the following reaction sequence?

Accepted Answer

A)  (R)-3-bromohexane 
B)  (S)-3-bromohexane 
C)  meso-3,4-dibromohexane 
D)  (±)-3,4-dibromohexane 
E)  2,3-dibromo-3-hexene 
A)  (R)-3-bromohexane 
B)  (S)-3-bromohexane 
C)  meso-3,4-dibromohexane 
D)  (±)-3,4-dibromohexane 
E)  2,3-dibromo-3-hexene

Question 4

Identify the product of the reaction of an alkyne with hydrogen and a metal catalyst.

Accepted Answer

A)  cis alkene 
B)  trans alkene 
C)  diene 
D)  alkyne 
E)  alkane 
A)  cis alkene 
B)  trans alkene 
C)  diene 
D)  alkyne 
E)  alkane

Question 5

For the reaction below, select the structure of the major organic product.

Accepted Answer

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

Question 6

What is the IUPAC name for the molecule shown below?

Accepted Answer

A)  2-methyl-5-propyl-3-heptyne 
B)  5-ethyl-2-methyl-3-octyne 
C)  1-isopropyl-3-ethyl-1-hexyne 
D)  6-methyl-3-propyl-4-heptyne 
E)  4-ethyl-7-methyl-5-octyne 
A)  2-methyl-5-propyl-3-heptyne 
B)  5-ethyl-2-methyl-3-octyne 
C)  1-isopropyl-3-ethyl-1-hexyne 
D)  6-methyl-3-propyl-4-heptyne 
E)  4-ethyl-7-methyl-5-octyne

Question 7

Which of the following is the structure for 3-sec-butyl-1-heptyne?

Accepted Answer

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

Question 8

Why would the following reaction sequence not produce the expected product shown?

Accepted Answer

A)  NaNH2 is used in the reduction of alkynes to trans alkenes. 
B)  The secondary alkyl halide would undergo an elimination reaction. 
C)  Br is not a good enough leaving group. 
D)  The terminal alkyne is not acidic enough to be deprotonated. 
E)  The reaction sequence is correct and will produce the shown product. 
A)  NaNH2 is used in the reduction of alkynes to trans alkenes. 
B)  The secondary alkyl halide would undergo an elimination reaction. 
C)  Br is not a good enough leaving group. 
D)  The terminal alkyne is not acidic enough to be deprotonated. 
E)  The reaction sequence is correct and will produce the shown product.

Question 9

What is the expected major product of the reaction sequence shown below? HC≡C:- + (CH3)2CHCH2Br $\to$ ?

Accepted Answer

A)  CH≡CH + (CH3)2CHC≡CH 
B)  (CH3)2CHC≡CCH3 
C)  (CH3)2CHCH2C≡CH 
D)  (CH3)2CHCHBrC≡CH 
E)  CH3CHCH2C≡CCH3 
A)  CH≡CH + (CH3)2CHC≡CH 
B)  (CH3)2CHC≡CCH3 
C)  (CH3)2CHCH2C≡CH 
D)  (CH3)2CHCHBrC≡CH 
E)  CH3CHCH2C≡CCH3

Question 10

Provide the IUPAC name for HC≡CCH2CH2CH3.

Accepted Answer

A)  pentyne 
B)  1-pentyne 
C)  butyne 
D)  1-butyne 
E)  2-butyne 
A)  pentyne 
B)  1-pentyne 
C)  butyne 
D)  1-butyne 
E)  2-butyne

Question 11

What mechanistic intermediate is used to explain the preference for addition of the Br atom, of HBr, to the internal carbon of a terminal alkyne?

Accepted Answer

A)  Formation of an intermediate with partial positive charge on a primary carbon 
B)  Formation of an intermediate with partial positive charge on a secondary carbon 
C)  Addition of the H atom to the carbon already with an H. 
D)  Addition of H, from HBr, to the least hindered carbon. 
E)  Steric hindrance for the approach of the Br atom to the primary carbon. 
A)  Formation of an intermediate with partial positive charge on a primary carbon 
B)  Formation of an intermediate with partial positive charge on a secondary carbon 
C)  Addition of the H atom to the carbon already with an H. 
D)  Addition of H, from HBr, to the least hindered carbon. 
E)  Steric hindrance for the approach of the Br atom to the primary carbon.

Question 12

Which sequence of reactions is expected to produce the product below as the final, and major, organic product?   I 1. HC≡CH, NaNH2; 2. (CH3)2CHCH2Br 3. Aqueous H2SO4, HgSO4 II 1. CH3C≡CH, NaNH2; 2. (CH3)2CHBr; 3. Disisamylborane; 4. H2O2, NaOH
III 1. (CH3)2CHBr, NaNH2; 2. CH3C≡CH; 3. O3; 4. H2O
IV 1. CH3C≡CH, NaNH2: 2. (CH3)2CHCH2Br; 3. BH3●THF; 4. H2O2, NaOH
V 1) (CH3)2CHCH2Br, NaNH2; 2. HC≡CH; 3. 9-BBN; 4. H2O2, NaOH

Accepted Answer

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

Question 13

What reagent(s) are required to prepare trans-2-heptene from 2-heptyne?

Accepted Answer

The answer of What reagent(s) are required to prepare trans-2-heptene...

Question 14

Which of the circled hydrogen atoms is the most acidic?

Accepted Answer

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

Question 15

Identify the expected major product from the treatment of 1-pentyne with 1 equivalent of HBr.

Accepted Answer

A)  1-bromo-1-pentene 
B)  2-bromo-1-pentene 
C)  1,1-dibromopentane 
D)  2,2-dibromopentane 
E)  1,2-dibromopentane 
A)  1-bromo-1-pentene 
B)  2-bromo-1-pentene 
C)  1,1-dibromopentane 
D)  2,2-dibromopentane 
E)  1,2-dibromopentane

Question 16

Which of the following is the acceptable structure for (R)-5-bromohept-2-yne?

Accepted Answer

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

Question 17

Provide the systematic IUPAC name for the molecule below: (CH3)3CCH2C≡CCH2CH(CH3)CH2CH3

Accepted Answer

A)  2,7,7-trimethyl-5-nonyne 
B)  2-ethyl-7,7-dimethyl-4-octyne 
C)  2,2,7-trimethyl-4-nonyne 
D)  7-ethyl-2,2-trimethyl-4-octyne 
E)  6-undecyne 
A)  2,7,7-trimethyl-5-nonyne 
B)  2-ethyl-7,7-dimethyl-4-octyne 
C)  2,2,7-trimethyl-4-nonyne 
D)  7-ethyl-2,2-trimethyl-4-octyne 
E)  6-undecyne

Exam 9: Alkynes

In an acid-catalyzed hydration, which of the following alkynes is expected to produce a single ketone?

Provide the IUPAC name for the alkyne expected to produce the two compounds listed below upon ozonolysis. CH3CH2CO2H and (CH3)3CCO2H

What is the final major product expected for the following reaction sequence?

Identify the product of the reaction of an alkyne with hydrogen and a metal catalyst.

For the reaction below, select the structure of the major organic product.

What is the IUPAC name for the molecule shown below?

Which of the following is the structure for 3-sec-butyl-1-heptyne?

Why would the following reaction sequence not produce the expected product shown?

What is the expected major product of the reaction sequence shown below? HC≡C:- + (CH3)2CHCH2Br →\to→ ?

Provide the IUPAC name for HC≡CCH2CH2CH3.

What mechanistic intermediate is used to explain the preference for addition of the Br atom, of HBr, to the internal carbon of a terminal alkyne?

What reagent(s) are required to prepare trans-2-heptene from 2-heptyne?

Which of the circled hydrogen atoms is the most acidic?

Identify the expected major product from the treatment of 1-pentyne with 1 equivalent of HBr.

Which of the following is the acceptable structure for (R)-5-bromohept-2-yne?

Provide the systematic IUPAC name for the molecule below: (CH3)3CCH2C≡CCH2CH(CH3)CH2CH3

A Review of General Chemistry: Electrons, Bonds, and Molecular Properties

Molecular Representations

Acids and Bases

Alkanes and Cycloalkanes

Stereoisomerism

Chemical Reactivity and Mechanisms

Alkyl Halides: Nucleophilic Substitution and Elimination Reactions

Addition Reactions of Alkenes

Radical Reactions

Synthesis

Alcohols and Phenols

Ethers and Epoxides; Thiols and Sulfides

Infrared Spectroscopy and Mass Spectrometry

Nuclear Magnetic Resonance Spectroscopy

Conjugated Pi Systems and Pericyclic Reactions

Aromatic Compounds

Aromatic Substitution Reactions

Aldehydes and Ketones

Carboxylic Acids and Their Derivatives

Alpha Carbon Chemistry: Enols and Enolates

Amines

Introduction to Organometallic Compounds

Carbohydrates

Amino Acids, Peptides, and Proteins

Lipids

Synthetic Polymers

Filters

Provide the IUPAC name for the alkyne expected to produce the two compounds listed below upon ozonolysis. CH₃CH₂CO₂H and (CH₃)₃CCO₂H

What is the expected major product of the reaction sequence shown below? HC≡C:^- + (CH₃)₂CHCH₂Br $\to$ ?

Provide the IUPAC name for HC≡CCH₂CH₂CH₃.

Provide the systematic IUPAC name for the molecule below: (CH₃)₃CCH₂C≡CCH₂CH(CH₃)CH₂CH₃