How many stereoisomers are possible for each of the following molecules?

(d)

How many stereoisomers are possible for each of the following molecules?

(e)

Which of the following compounds are meso?

(a)

Which of the following compounds are meso?

(c)

Which of the following compounds are meso?

(e)

Which of the following compounds are meso?

(f)

Which of the following compounds are meso?

(g)

How many stereoisomers are possible for each of the following molecules?

(a)

How many stereoisomers are possible for each of the following molecules?

(b)

Which of the following diastereomers of hexane-2,5-diol is optically inactive? Why?

(i) Which of the following pairs of compounds would you expect to have different physical properties?

(ii) What is the relationship between each of the pairs?

(iii) Assign the absolute configuration of each stereocenter to confirm your answer.

(a)

(i) Which of the following pairs of compounds would you expect to have different physical properties?

(ii) What is the relationship between each of the pairs?

(iii) Assign the absolute configuration of each stereocenter to confirm your answer.

(b)

(i) Which of the following pairs of compounds would you expect to have different physical properties?

(ii) What is the relationship between each of the pairs?

(iii) Assign the absolute configuration of each stereocenter to confirm your answer.

(c)

Convert the Fischer projections into line-angle drawings and assign (R) and (S) at each chiral center.

(a)

Convert the Fischer projections into line-angle drawings and assign (R) and (S) at each chiral center.

(c)

Convert the line-angle drawings into Fischer projections.

(a)

Convert the line-angle drawings into Fischer projections.

(b)

Convert the line-angle drawings into Fischer projections.

(c)

How might you separate enantiomers of 2-phenylpropionic acid?

Figure 6.52 <IMAGE> shows the lipase-catalyzed kinetic resolution of secondary alcohols. Show a reaction coordinate diagram that rationalizes the results obtained.

We discuss the reaction of Grignard reagents (organomagnesium compounds) to ketones in Chapter 17. Mechanistically, the reaction proceeds by the nucleophilic addition of a methyl carbanion to the electrophilic carbon of the carbonyl, breaking the C―Oπ bond, resulting in an alkoxide intermediate that is subsequently protonated to produce the 3° alcohol.

(a) Why does this reaction produce a racemic mixture of 3° alcohols?

We discuss the reaction of Grignard reagents (organomagnesium compounds) to ketones in Chapter 17. Mechanistically, the reaction proceeds by the nucleophilic addition of a methyl carbanion to the electrophilic carbon of the carbonyl, breaking the C―Oπ bond, resulting in an alkoxide intermediate that is subsequently protonated to produce the 3° alcohol.

(b) Why, when the substrate is modified slightly, does the reaction result in an excess of one stereoisomer?

Classify the following objects and molecules as chiral or achiral.

(a) <IMAGE>

Classify the following objects and molecules as chiral or achiral.

(c) <IMAGE>

Classify the following objects and molecules as chiral or achiral.

(e)

Classify the following objects and molecules as chiral or achiral.

(h)

Classify the following objects and molecules as chiral or achiral.

(k)

Classify the following objects and molecules as chiral or achiral.

(l)

Define the relationship between each set of two molecules as chain isomers, positional isomers, functional group isomers, enantiomers, diastereomers, conformational isomers, or identical

(a)

Define the relationship between each set of two molecules as chain isomers, positional isomers, functional group isomers, enantiomers, diastereomers, conformational isomers, or identical.

(c)