Question 1

Consider the reaction coordinate diagram with points A, B, C, D, E, F, G, H, and I. Which letters correspond to the transition states in the reaction pathway?

Accepted Answer

B, D, F, and H

Question 2

Given the reaction coordinate diagram, which intermediate is the most stable?

Accepted Answer

I

Question 3

Which of the following bases can deprotonate propanoic acid ($$pK_a = 4.88) in a $$reaction that favors product formation?

Accepted Answer

(i) CH$$_3O$^-$$, (ii) NH$$_3$$, (iii) CH$$_3C$	ext{≡}C$^-$$

Question 4

At which carbon would an electrophile attach in hex-1-en-5-yne, and why?

Accepted Answer

Carbon 1, due to the formation of a more stable carbocation.

Question 5

An unknown alkyne gives dodecanedioic acid after oxidative cleavage with $$\mathrm{$$OsO_4$$}$$ and $$\mathrm{H_2O}. $$Which structure is most likely for the unknown alkyne?

Accepted Answer

$$\mathrm{H_3C(CH_2$)_4C\equiv C(CH_2$)_4CH_3}$$

Question 6

Which product is expected from the oxymercuration–demercuration of 1-ethyl-4-methylcyclohexene?

Accepted Answer

2-ethyl-4-methylcyclohexanol

Question 7

When 1-methylcyclohexene reacts with $$\mathrm{H_2SO_4}$$ and $$\mathrm{H_2O}$$, which product is formed?

Accepted Answer

2-methylcyclohexanol

Question 8

Why does ring opening occur in opposite directions in the two reactions shown, one with a tetraalkylammonium group and one with an ethoxy group?

Accepted Answer

For Reaction 1, ring opening occurs in the indicated direction because the tetraalkylammonium group can stabilize positive charge. For Reaction 2, ring opening occurs in the indicated direction because the ethoxy group is a weaker electron donating group compared to the tetraalkylammonium group.

Question 9

What is the expected product when 4-ethylstyrene is treated with excess hot, concentrated potassium permanganate ($$\mathrm{$$KMnO_4$$}$$)?

Accepted Answer

Benzoic acid and acetic acid

Question 10

Which statement best explains why the $$\mathrm{S_N2}$$ reaction of a 1° bromide by alkynide fails to give the desired product when the substrate contains an acidic alcoholic proton?

Accepted Answer

Due to the presence of an acidic alcoholic proton in the substrate, an acid-base reaction will occur instead of a substitution reaction.

Question 11

Which of the following statements about the bond dissociation energy of C–Br bonds in different environments is correct?

Accepted Answer

A C–Br bond on a primary carbon will have a higher bond dissociation energy than on a tertiary carbon.

Question 12

Which step in the reaction coordinate diagram is the fastest?

Accepted Answer

The step with the lowest activation energy barrier.

Question 13

Which of the following alkenes will only generate 2-bromo-3,3-dimethylpentane after reaction with HBr?

Accepted Answer

3,3-dimethyl-2-pentene

Question 14

What is the product when 3-methyl-1-butyne is treated with H$$_2$$ and Pd/C?

Accepted Answer

3-methylbutane

Question 15

Which acetylide ion and carbonyl compound can be used to synthesize 3,7-dimethyloct-4-yn-3-ol?

Accepted Answer

2,6-dimethylhex-3-yn-1-ide and propanal

Question 16

Which of the following is the expected product when but-1-yne is treated with $$\mathrm{$$NaNH_2$$}$$?

Accepted Answer

But-1-yne anion ($$\mathrm{CH_3C\equiv C^-CH_3$})$$

Question 17

Which of the following is the major product when but-1-yne is treated with $$\mathrm{$$HgSO_4$$/H_2SO_4, H_2O}$$?

Accepted Answer

2-butanone

Question 18

Which of the following is the major product when but-1-yne is treated with $$\mathrm{Sia_2BH}$$ followed by $$\mathrm{H_2O_2, OH^-}$$?

Accepted Answer

Butanal

Question 19

Which statement best describes the regioselectivity of halohydrin formation from an alkene with Br$$_2$$ and H$$_2O$$?

Accepted Answer

The OH group attaches to the more substituted carbon due to the formation of a more stable bromonium ion intermediate.

Advanced General Chemistry: Reaction Mechanisms, Acid-Base Chemistry, and Organic Transformations

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