Question 1

Which of the following is the correct IUPAC name for the ether with the structure $$CH_3OCH_2CH_3$$?

Accepted Answer

Methoxyethane

Question 2

Which reagent is commonly used for the formation of epoxides from alkenes in a laboratory setting?

Accepted Answer

mCPBA

Question 3

In the Williamson Ether Synthesis, which combination of reactants is most appropriate for synthesizing tert-butyl ethyl ether?

Accepted Answer

Tert-butoxide ion and ethyl bromide

Question 4

What is the critical intermediate formed during alkoxymercuration of an alkene?

Accepted Answer

Mercurinium ion

Question 5

Which of the following best describes the mechanism of acid-catalyzed ether synthesis from alcohols?

Accepted Answer

Protonation of alcohol, followed by nucleophilic attack by another alcohol molecule

Question 6

When an epoxide reacts under acidic conditions, which carbon is attacked by the nucleophile?

Accepted Answer

The more substituted carbon

Question 7

Which statement about the reaction of a Grignard reagent with an epoxide is correct?

Accepted Answer

The Grignard reagent attacks the less substituted carbon of the epoxide, resulting in chain extension

Question 8

Which of the following is a requirement for the Williamson Ether Synthesis to proceed efficiently?

Accepted Answer

Use of a primary alkyl halide

Question 9

How is a halohydrin converted into an epoxide?

Accepted Answer

Treatment with a base to induce intramolecular nucleophilic substitution

Question 10

In the addition of $$HX to 1$$,3-butadiene, which product is favored at low temperature?

Accepted Answer

1,2-adduct (kinetic product)

Question 11

Which of the following best explains why conjugated dienes are more stable than isolated dienes?

Accepted Answer

Delocalization of electrons across the conjugated system lowers the overall energy

Question 12

Which of the following correctly describes the regioselectivity of epoxide opening under basic conditions?

Accepted Answer

Nucleophile attacks the less substituted carbon

Question 13

In the reaction energy diagram for $$HX$$ addition to a diene, what does the intermediate represent?

Accepted Answer

An allylic carbocation

Question 14

Which of the following is NOT a requirement for acid-catalyzed ether synthesis?

Accepted Answer

Use of a tertiary alcohol

Question 15

What is the major product when 1,3-butadiene reacts with $$HBr at $$high temperature?

Accepted Answer

1,4-adduct (thermodynamic product)

Question 16

Which molecular orbital interaction is responsible for the stability of conjugated dienes?

Accepted Answer

Overlap of $$p$$ orbitals across adjacent double bonds

Question 17

Which of the following statements about the mechanism of epoxide formation from halohydrins is correct?

Accepted Answer

The base deprotonates the alcohol, which then attacks the adjacent carbon bearing the halide

Question 18

Which of the following is a plausible reason for the failure of Williamson Ether Synthesis when using a tertiary alkyl halide?

Accepted Answer

Elimination (E2) competes with substitution (SN2) due to steric hindrance

Question 19

In the alkoxymercuration reaction, what is the role of $$Hg(OAc)_2$$?

Accepted Answer

It activates the alkene for nucleophilic attack by forming a mercurinium ion

Question 20

Which of the following best describes the difference between kinetic and thermodynamic products in $$HX$$ addition to dienes?

Accepted Answer

Kinetic product forms faster and is favored at low temperature; thermodynamic product is more stable and favored at high temperature

Ethers, Epoxides, and Dienes: Synthesis, Reactions, and Mechanisms

Guida di studio - Domande di pratica