Question 1

Which of the following statements best explains why E2 reactions with bulky bases favor the formation of less substituted alkenes (Hofmann product) rather than the more substituted alkenes (Zaitsev product)?

Accepted Answer

Bulky bases are less able to abstract the more hindered beta-hydrogen, so they remove the more accessible hydrogen, leading to the less substituted alkene.

Question 2

Which of the following alkyl halides will react fastest in an SN2 reaction with a strong nucleophile such as $$\mathrm{NaOH}$$?

Accepted Answer

1-bromopropane

Question 3

A chemist treats 2-bromobutane with a strong base ($$\mathrm{NaOEt}) in $$ethanol. Which is the major product, and what rule explains this outcome?

Accepted Answer

2-butene, due to Zaitsev's rule favoring the more substituted alkene

Question 4

Which of the following statements about the E1 elimination mechanism is correct?

Accepted Answer

The rate-determining step is the loss of the leaving group to form a carbocation intermediate.

Question 5

Which of the following best describes the product of acid-catalyzed dehydration of 2-methyl-2-butanol?

Accepted Answer

2-methyl-2-butene, because the more substituted alkene is favored (Zaitsev product)

Question 6

Which of the following statements about aromaticity is FALSE?

Accepted Answer

Cyclohexane is aromatic because it is a six-membered ring.

Question 7

Which of the following is the correct order of reactivity for alkyl halides in SN1 reactions?

Accepted Answer

Tertiary \u003e Secondary \u003e Primary

Question 8

A solution of 1-bromopropane is treated with aqueous $$\mathrm{NaOH}. $$Which mechanism is most likely, and what is the major product?

Accepted Answer

SN2 mechanism, producing 1-propanol

Question 9

Which of the following statements about the acid-catalyzed opening of epoxides is correct?

Accepted Answer

The nucleophile attacks the more substituted carbon of the epoxide ring.

Question 10

Which of the following best explains why tertiary alcohols are more reactive than primary alcohols toward acid-catalyzed dehydration?

Accepted Answer

Tertiary carbocations are more stable than primary carbocations, making the reaction faster.

Question 11

Which of the following is a correct statement about the alkylation of amines?

Accepted Answer

Alkylation of a primary amine with excess alkyl halide can lead to a quaternary ammonium salt via multiple SN2 reactions.

Question 12

Which of the following statements about the Friedel–Crafts alkylation reaction is correct?

Accepted Answer

It involves the generation of a carbocation intermediate that reacts with an aromatic ring.

Question 13

Which of the following is the correct statement about the effect of resonance on the acidity of phenol compared to cyclohexanol?

Accepted Answer

Phenol is more acidic because the phenoxide ion is stabilized by resonance.

Question 14

Which of the following best describes the product of the reaction of benzene with $$\mathrm{Br_2$} in $$the presence of $$\mathrm{$$FeBr_3$$}$$?

Accepted Answer

Bromobenzene, via electrophilic aromatic substitution

Question 15

Which of the following is a feature of anti-aromatic compounds?

Accepted Answer

They have $$4n$$ $$\pi$$ electrons and are less stable than their acyclic analogs.

Question 16

A chemist wants to convert 1-butanol to 1-bromobutane. Which reagents should be used?

Accepted Answer

$$\mathrm{HBr}$$

Question 17

Which of the following statements about the stereochemistry of E2 eliminations is correct?

Accepted Answer

E2 eliminations require the hydrogen and leaving group to be anti-periplanar.

Question 18

Which of the following is the correct statement about the reactivity of amines in alkylation reactions?

Accepted Answer

Tertiary amines are less nucleophilic than primary amines due to steric hindrance.

Question 19

Which of the following is a correct statement about the effect of solvents on SN1 and SN2 reactions?

Accepted Answer

Polar protic solvents favor SN1 reactions, while polar aprotic solvents favor SN2 reactions.

Organic Chemistry: Elimination, Substitution, Alcohols, Amines, Aromaticity, and Related Mechanisms

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