Question 1

Which of the following statements best describes the difference between enantiomers and diastereomers?

Accepted Answer

Enantiomers are non-superimposable mirror images, while diastereomers are stereoisomers that are not mirror images.

Question 2

Which of the following reagents would you use to convert benzene into nitrobenzene as the first step in a multi-step synthesis?

Accepted Answer

$$\mathrm{$$HNO_3$$}$$ and $$\mathrm{H_2SO_4}$$

Question 3

Which of the following best describes the product when $$\mathrm{(CH_3$)_2CuLi}$$ reacts with 1-bromopropene?

Accepted Answer

A methyl group replaces the bromine atom, forming 2-methylpropene.

Question 4

Which of the following is the correct IUPAC name for the compound shown below? (Assume the structure is a six-carbon chain with a methyl group at C-3 and a hydroxyl group at C-3.)

Accepted Answer

3-methylhexan-3-ol

Question 5

A Grignard reagent is prepared from bromobenzene and magnesium in ether. Which carbonyl compound should be reacted with this Grignard reagent to synthesize 1,1-diphenylethanol?

Accepted Answer

Acetaldehyde ($$\mathrm{CH_3CHO})$$

Question 6

Which of the following statements about the reaction mechanism of nucleophilic addition to a carbonyl group is correct?

Accepted Answer

The nucleophile attacks the electrophilic carbon of the carbonyl, forming a tetrahedral intermediate.

Question 7

Which of the following sequences would best synthesize 2-phenylpentan-2-ol from benzene?

Accepted Answer

Friedel-Crafts alkylation to form ethylbenzene, oxidation to acetophenone, Grignard addition of ethylmagnesium bromide, then acid workup.

Question 8

Which of the following best describes the stereochemical outcome when a Grignard reagent reacts with a prochiral ketone?

Accepted Answer

A racemic mixture of alcohols is formed if the ketone is unsymmetrical.

Question 9

Which of the following is the correct mechanism for the reaction of $$\mathrm{(CH_3$)_2CuLi}$$ with an $$\alpha,\beta-$$unsaturated ketone?

Accepted Answer

Conjugate (1,4-) addition of a methyl group to the $$\beta-$$carbon.

Question 10

Which of the following statements about the reactivity of Grignard reagents is correct?

Accepted Answer

Grignard reagents react with esters to give tertiary alcohols after two additions.

Question 11

Which of the following is a valid reason why $$\mathrm{(CH_3$)_2CuLi} is $$less reactive than a Grignard reagent?

Accepted Answer

$$\mathrm{(CH_3$)_2CuLi} is $$less basic and less nucleophilic due to the presence of copper.

Question 12

Which of the following best describes the product of the reaction between benzene and propionyl chloride ($$\mathrm{CH_3CH_2COCl}) in $$the presence of $$\mathrm{$$AlCl_3$$}$$?

Accepted Answer

Propiophenone ($$\mathrm{C_6H_5COCH_2CH_3})$$

Question 13

Which of the following is the correct sequence of reagents to convert benzene to p-bromoaniline?

Accepted Answer

Nitration, bromination, reduction

Question 14

Which of the following statements about the stereochemistry of reactions involving cyclic ketones and Grignard reagents is correct?

Accepted Answer

Attack can occur from either face of the planar carbonyl, leading to cis and trans isomers.

Question 15

Which of the following is the best method to synthesize heptan-4-ol using a Grignard reagent?

Accepted Answer

Reacting propylmagnesium bromide with butanal, followed by acid workup.

Question 16

Which of the following is a correct statement about the selectivity of $$\mathrm{(CH_3$)_2CuLi} in $$organic synthesis?

Accepted Answer

$$\mathrm{(CH_3$)_2CuLi}$$ selectively reacts with acid chlorides to give ketones.

Question 17

Which of the following is the correct product when benzene is treated with methyl chloride ($$\mathrm{CH_3Cl}) $$and $$\mathrm{$$AlCl_3$$}$$?

Accepted Answer

Toluene ($$\mathrm{C_6H_5CH_3})$$

Question 18

Which of the following is the best explanation for why Grignard reagents must be prepared and used under anhydrous conditions?

Accepted Answer

Grignard reagents react rapidly with water to form alkanes and lose their nucleophilicity.

Question 19

Which of the following is the correct product when $$\mathrm{(CH_3$)_2CuLi}$$ reacts with 1-bromobutane?

Accepted Answer

1-methylbutane

Question 20

Which of the following best describes the outcome when a Grignard reagent reacts with an ester?

Accepted Answer

Two equivalents of the Grignard reagent add to the ester, forming a tertiary alcohol after hydrolysis.

Organic Chemistry 2 Exam Study Guidance

Guida di studio - Domande di pratica

Study guide - Flashcard