Question 1

Which of the following statements best explains why tertiary alcohols cannot be oxidized under typical laboratory conditions?

Accepted Answer

Tertiary alcohols lack a hydrogen atom on the carbon bearing the hydroxyl group, which is necessary for oxidation to occur.

Question 2

A student treats 2-butanol with $$\mathrm{$$PBr_3$$}. $$What is the expected stereochemical outcome at the chiral center if the starting alcohol is optically active?

Accepted Answer

Inversion of configuration due to an $$\mathrm{S_N2}$$ mechanism.

Question 3

Which of the following reagents would you use to selectively oxidize a primary alcohol to an aldehyde without further oxidation to a carboxylic acid?

Accepted Answer

Pyridinium chlorochromate (PCC)

Question 4

Which of the following best describes the role of sodium hydride ($$\mathrm{NaH}) in $$the Williamson ether synthesis?

Accepted Answer

It deprotonates the alcohol to generate a nucleophilic alkoxide.

Question 5

A chemist wants to protect a primary alcohol during a multi-step synthesis. Which reagent would be most appropriate to convert the alcohol into a silyl ether protecting group?

Accepted Answer

TBSCl (tert-butyldimethylsilyl chloride) and Et$$_3N$$

Question 6

Which of the following alcohols is most soluble in water?

Accepted Answer

Methanol ($$\mathrm{CH_3OH})$$

Question 7

Which of the following statements about the acid-catalyzed dehydration of alcohols is correct?

Accepted Answer

The reaction proceeds via an $$\mathrm{E1}$$ mechanism for secondary and tertiary alcohols, forming the most substituted alkene.

Question 8

Which of the following is the correct order of boiling points for the compounds: ethanol, diethyl ether, and propane?

Accepted Answer

$$\mathrm{ethanol \u003e diethyl\ ether \u003e propane}$$

Question 9

Which of the following statements about the reaction of ethers with HI or HBr is correct?

Accepted Answer

Cleavage occurs at the less substituted carbon via $$\mathrm{S_N2} if $$both ether carbons are methyl or primary.

Question 10

A chemist treats a cis-2-butene with mCPBA. What is the stereochemistry of the resulting epoxide?

Accepted Answer

A cis-epoxide is formed due to the stereospecific nature of the reaction.

Question 11

Which of the following best describes the outcome when a chiral secondary alcohol is converted to a tosylate using TsCl and pyridine, then subjected to an $$\mathrm{S_N2}$$ reaction with NaI?

Accepted Answer

Net inversion of configuration at the chiral center.

Question 12

Which of the following is the best explanation for why ethers are commonly used as solvents in organic reactions?

Accepted Answer

They are relatively inert and can coordinate cations, enhancing solubility and reactivity.

Question 13

Which of the following reagents is used to remove a TBS (tert-butyldimethylsilyl) protecting group from an alcohol?

Accepted Answer

Tetrabutylammonium fluoride (TBAF)

Question 14

Which of the following statements about the nucleophilic ring opening of epoxides is correct?

Accepted Answer

A nucleophile attacks the less substituted carbon via an $$\mathrm{S_N2}$$ mechanism, resulting in inversion of configuration.

Question 15

Which of the following is the correct product when 1,2-ethanediol (ethylene glycol) is treated with periodic acid ($$\mathrm{$$HIO_4$$}$$)?

Accepted Answer

Two molecules of formaldehyde ($$\mathrm{H_2C=O})$$

Question 16

Which of the following best describes the effect of branching on the boiling point of alcohols?

Accepted Answer

Branching decreases the boiling point by reducing surface area and hydrogen bonding.

Question 17

Which of the following is the correct sequence of steps for the preparation of an unsymmetrical ether using the Williamson ether synthesis?

Accepted Answer

Deprotonate the less hindered alcohol with NaH, then react with the more hindered alkyl halide.

Question 18

Which of the following statements about the reaction of a 1,2-bromohydrin with NaH is correct?

Accepted Answer

It forms an epoxide via an intramolecular $$\mathrm{S_N2}$$ reaction.

Question 19

Which of the following is the best description of the term 'amphiprotic' as it applies to alcohols?

Accepted Answer

Alcohols can act as both hydrogen bond donors and acceptors.

Question 20

Which of the following reagents would you use to convert a primary alcohol to a carboxylic acid in a single step?

Accepted Answer

Jones reagent ($$\mathrm{$$CrO_3$$}$$, $$\mathrm{H_2SO_4})$$

Comprehensive Study Guide: Alcohols, Ethers, and Epoxides (Chapters 10 & 11) and Key Organic Chemistry Concepts

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