TEST 3: Chapter 21

What is the product of the following reaction? A. I B. II C. III D. IV

D

What is the structure of 2-trifluoromethyl-2-methoxybutanal? A. I B. II C. III D. IV

D

Cyclic acetals are used as protecting groups for ketones or aldehydes because they are inert to all of the following reagents except A. aqueous acid. B. aqueous base. C. oxidizing reagents. D. reducing reagents.

A

Identify how you could synthesize an enamine. A. React a ketone or an aldehyde with a secondary amine. B. React a ketone or an aldehyde with a primary amine. C. React a ylide with a primary amine. D. React a ylide with a secondary amine.

A

What is (are) the product(s) of the following reaction? A. I only B. II only C. III only D. II and III

A

What is the product of the following reaction? A. I B. II C. III D. IV

A

What is the product of the following reactions? A. I B. II C. III D. IV

A

What is the product of the following sequence of reactions? A. I B. II C. III D. IV

A

What product is formed when the following compound is hydrolyzed with aqueous acid? A. I B. II C. III D. IV

A

What would you use to prepare the following ylide from the starting phosphonium salt? A. Butyl lithium B. 1-Bromo-2-methylpropane C. Triphenylphosphine D. Acetic acid

A

Which of the following oxidants would work for the following reaction? A. H2Cr2O7 B. FeCl3 C. I2 D. Ag2O

A

Which of the following will have the highest wave number for the carbonyl stretch in the IR spectrum? A. I B. II C. III D. IV

A

Why can't you use acidic conditions (such as aqueous hydrochloric acid) for the addition of a Grignard reagent to a ketone? A. Because the Grignard reagent will react with the acid and be quenched B. Because the ketone will be protonated and thus unreactive C. Because the ketone will form an unreactive enol D. Because the Grignard reagent won't dissolve in aqueous solutions

A

What is the cyclic hemiacetal product formed from intramolecular cyclization of the following hydroxy aldehyde? A. I B. II C. III D. IV

B

Using 1H NMR spectroscopy, how can you tell the difference between an aldehyde and a ketone? A. An aldehyde has a C-H stretch (one or two) between 2700-2830 cm-1. B. An aldehyde has a proton signal between 9-10 ppm. C. A ketone has signals around 2-3 ppm. D. A ketone has a signal around 200 ppm.

B

What is the IUPAC name for the following compound? A. Pivaldehyde B. 2,2-Dimethylpropanal C. Tert-butyl aldehyde D. 2,2-Dimethylpentanal

B

What is the missing reagent in the reaction below? A. Ethyl amine, mild acid B. Diethylamine, mild acid C. Diethylamine, strong acid D. Diethylamine, NaOMe

B

What is the missing reagent in the reaction below? A. Methanol, acid B. Ethanol, acid C. NaOEt D. NaOMe

B

What is the product of the following reaction? A. I B. II C. III D. IV

B

What is the product of the following reaction? A. I B. II C. III D. IV

B

What is the product? A. I B. II C. III D. IV

B

What is the structure of 3-methylcyclohexanone? A. I B. II C. III D. IV

B

What is the structure of benzophenone? A. I B. II C. III D. IV

B

What needs to be done to make the following reaction go to starting materials? A. Heat the reaction. B. Add aqueous acid. C. Add aqueous base. D. Add water.

B

Why are strongly acidic conditions not used in the formation of enamines and imines? A. The carbonyl will be protonated. B. The amine will be completely protonated. C. The product is not stable to strong acid. D. An enol will be formed.

B

Butanal (MW= 72) has a boiling point of 76 °C while butanol (MW= 74) has a boiling point of 118 °C. What accounts for this difference in boiling points? A. Butanol is polar while butanal is not polar. B. Butanol can exhibit dipole-dipole interactions while butanal cannot. C. Butanol can hydrogen bond and butanal cannot hydrogen bond. D. Butanal is less sterically hindered than butanol.

C

Name the following aldehyde. A. 1-Methylcyclopentanal B. 2-Methylcyclopentanal C. 2-Methylcyclopentanecarbaldehyde D. 1-Methylcyclopentanylcarbaldehyde

C

Using IR spectroscopy, how can you tell the difference between a ketone and an aldehyde? A. A ketone has no carbonyl stretch at 1720 cm-1. B. An aldehyde has a carbonyl stretch at 1820 cm-1. C. An aldehyde has two C-H stretches between 2700-2850 cm-1. D. A ketone has no C-H stretches.

C

What compound is consistent with the following 1H NMR spectrum? A. Acetone B. Propanal C. Cyclobutanone D. 2-butanone

C

What is the driving force for the Wittig reaction? A. The formation of an alkene B. The deprotonation of a phosphonium salt C. The elimination of triphenylphosphine oxide D. The formation of a phosphonium salt

C

What is the major organic product obtained from the following sequence of reactions? A. I B. II C. III D. IV

C

What is the missing reagent in the reaction below? A. I B. II C. III D. IV

C

What is the product of the following reaction? A. I B. II C. III D. IV

C

What product is formed when the following acetal is hydrolyzed with aqueous acid? A. I B. II C. III D. IV

C

What sequence of reactions is required for the following transformation? A. [1] NaOMe, [2] acetone B. [1] Ph3P, [2] acetone C. [1] Ph3P, [2] KOtBu, [3] acetone D. Acetone, heat

C

Which of the following statements about carbohydrates is not true? A. Carbohydrates are sugars and starches. B. Carbohydrates often contain acetals and hemiacetals. C. In solution, glucose is in the cyclic acetal form only. D. Glucose can form a cyclic hemiacetal from the acyclic polyhydroxy aldehyde.

C

How would the following compounds be distinguishable using IR and 1H NMR spectroscopy? A. The 1H NMR spectrum of compound I will have two singlets. B. The C=O absorption in the IR spectrum of compound I will be at a higher wave number than that of compound II. C. The 1H NMR spectrum of compound II will have one triplet at a chemical shift of about 4. D. The 1H NMR spectrum of compound I will have two singlets AND the C=O absorption in the IR spectrum of compound I will be at a higher wave number than that of compound II.

D

Is the following reaction reversible and, if so, under what conditions? A. No B. Yes, under acidic conditions C. Yes, using Pd/C D. Yes, under basic conditions

D

What is (are) the product(s) of the following reaction? A. I only B. II only C. III only D. II and III

D

What is the IUPAC for the following compound? A. 1-Formyl-2-nitropropane B. 1-Formyl-3-nitrobutane C. 2-Nitrobutanal D. 3-Nitrobutanal

D

What is the first step in nucleophilic addition under acidic conditions? A. Protonation of the nucleophile B. Addition of the nucleophile C. Loss of water D. Protonation of the carbonyl

D

What needs to be done to make the following reaction proceed? A. Heat the reaction. B. Add an acid catalyst only. C. Add a base catalyst only. D. Heat the reaction and add an acid catalyst.

D

When an aldehyde is reacted with excess ethanol with an acid as a catalyst, what is the product called? A. Hemiacetal B. Di-ether C. Di-alkoxy alkane D. Acetal

D

Which of the following products is (are) formed by Wittig reaction of CH3CH2CH2CHO with Ph3P CHCH3? A. Only I B. Only II C. Only III D. Only I and II

D

Which is the most reactive carbonyl compound? A. I B. II C. III D. IV

a