Question 1

Which of the following statements best explains why ethers have lower boiling points than alcohols of comparable molecular weight?

Accepted Answer

Ethers cannot form hydrogen bonds with themselves, while alcohols can.

Question 2

Arrange the following compounds in order of increasing solubility in water: Hexane, Diethyl ether, Ethylene glycol dimethyl ether.

Accepted Answer

Hexane \u003c Diethyl ether \u003c Ethylene glycol dimethyl ether

Question 3

Which of the following is the best method to synthesize tert-butyl methyl ether using the Williamson ether synthesis?

Accepted Answer

React potassium tert-butoxide with methyl bromide.

Question 4

What is the major product when 2-bromo-2-methylpropane reacts with sodium methoxide?

Accepted Answer

2-Methylpropene

Question 5

Which of the following best describes the acid-catalyzed dehydration of ethanol to form diethyl ether?

Accepted Answer

It is an intermolecular reaction that gives high yields for symmetrical ethers from unbranched primary alcohols.

Question 6

Which functional group characterizes an epoxide?

Accepted Answer

A three-membered cyclic ether containing an oxygen atom.

Question 7

What is the product of the following reaction: $$2 \mathrm{CH}_2=\mathrm{CH}_2 + \mathrm{O}_2 \xrightarrow{Ag} 2 \mathrm{H}_2\mathrm{C}-\mathrm{CH}_2\mathrm{O}$$?

Accepted Answer

Oxirane (Ethylene oxide)

Question 8

Which reagent is commonly used for laboratory epoxidation of alkenes?

Accepted Answer

Peroxycarboxylic acid (e.g., mCPBA)

Question 9

Epoxidation of cis-2-butene with a peroxycarboxylic acid produces:

Accepted Answer

A meso compound: cis-2,3-dimethyloxirane

Question 10

During acid-catalyzed ring opening of an epoxide, nucleophilic attack occurs:

Accepted Answer

At the carbon better able to bear a partial positive charge, with anti stereoselectivity.

Question 11

Which of the following is the sulfur analog of an ether?

Accepted Answer

Sulfide (thioether)

Question 12

What is the product when methyl phenyl sulfide is treated with one mole of 30% aqueous hydrogen peroxide at room temperature?

Accepted Answer

Methyl phenyl sulfoxide

Question 13

Which of the following reactions is a direct application of nucleophilic substitution for the preparation of cyclic sulfides?

Accepted Answer

Treating 1,4-dichlorobutane with Na2S to form thiolane (tetrahydrothiophene)

Question 14

Which compound is formed by acid-catalyzed hydrolysis of oxirane (ethylene oxide)?

Accepted Answer

1,2-Ethanediol (Ethylene glycol)

Question 15

Which of the following best describes the stereochemistry of glycol formation from acid-catalyzed hydrolysis of an epoxide?

Accepted Answer

The nucleophile attacks with anti stereoselectivity, resulting in a trans diol.

Question 16

Which of the following is the correct IUPAC name for the compound with the structure $$\mathrm{CH}_3\mathrm{CH}_2\mathrm{S}\mathrm{CH}_2\mathrm{CH}_3$$?

Accepted Answer

Ethylsulfanylethane (Diethyl sulfide)

Question 17

Which compound is produced by oxidation of dimethyl sulfide with oxides of nitrogen?

Accepted Answer

Dimethyl sulfoxide

Question 18

Which of the following is a characteristic feature of epoxide ring-opening reactions?

Accepted Answer

Nucleophilic substitution at one of the carbons of the epoxide ring with the oxygen atom as the leaving group.

Question 19

Which compound is formed when 1,2-epoxycyclopentane is hydrolyzed in the presence of acid?

Accepted Answer

trans-1,2-Cyclopentanediol (a racemic mixture)

Ethers, Epoxides, and Sulfides: Structure, Properties, Synthesis, and Reactions

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