chem231 exam 2 practice

1. Is this chiral or achiral?

2. If chiral, label chiral center with *

1. Is this chiral or achiral?

2. If chiral, label chiral center with *

1. Are these molecules chiral?

2. What is their relationship?

1. Are these molecules chiral?

2. What is their relationship?

1. What is the relationship between this pair?

2. How do you know?

1. What is the relationship between this pair?

2. How do you know?

1. Nomenclate the following molecule

2. Add the R/S configuration in the right location

1-bromo-1-fluropropane

1. Nomenclate the following molecules

2. Add the R/S configuration in the right locations

3. Are they the same molecule?

3. No, they have different R/S configurations

Assign the R/S configuration to the chiral center

Assign the R/S configuration to the chiral center

Assign the R/S configuration to the chiral center

Assign the R/S configuration to the chiral center

Assign the R/S configuration to the chiral center

Assign the R/S configuration to the chiral center

Find the stereochemical relationship between each of these molecules (hint: assign R/S)

Find the stereochemical relationship between these molecules (hint: alkenes)

Find the stereochemical relationship between these molecules (hint: alkenes)

Find the stereochemical relationship between these molecules (hint: alkenes)

Find the stereochemical relationship between these molecules (hint: alkenes)

identical → neither E or Z

Draw one diastereomer of the molecule

Draw one diastereomer of the molecule

Find the stereochemical relationship between each of these molecules

Are the following compounds identical, constitutional isomers, enantiomers, or diastereomers? Use whatever method works for you.

Are the following compounds identical, constitutional isomers, enantiomers, or diastereomers? Use whatever method works for you.

Are the following compounds identical, constitutional isomers, enantiomers, or diastereomers? Use whatever method works for you.

Are the following compounds identical, constitutional isomers, enantiomers, or diastereomers? Use whatever method works for you.

Convert this molecule to a Fischer Projection

Convert this Fischer Projection into a basic structure

1. Convert this molecule to a Fischer Projection (FP)

2. Conver the FP into a skeletal structure (hint: rotate skeletal)

to skeletal

• vertical axis → plane (solid line)

• 1 side is dashed, the other is wedged

• “tip” on its side

• want carbons in zig zag formation

Convert skeletal to NP to FP

Assign R/S from Fischer Projection

Which substituent forms the most stable product?

perform the 3-step mechanism of the halogenation of alkanes

1. What is the product of this reaction?

2. Show all steps (hint: halogenation)

Which hydrogen would for the most stable radical?

Find the product of this reaction

• hint: organometallic compounds

Find the product of this reaction

• hint: organometallic compounds

1. Find the product of this reaction

2. Which side does equilibrium go to?

• hint: organometallic compounds

1. Find the product of this reaction

2. Which side does equilibrium go to?

• hint: organometallic compounds

1. fill in the products

2. will the following reaction proceed as written?

• No

which of these reactions is better/would happen faster and why?

which is a strong/better nucleophile?

which is a strong/better nucleophile?

which is a strong/better nucleophile?

1. what is the reaction scheme?

2. find the products

1. SN2

1. what is the reaction scheme?

2. find the products

1. SN2

• backside attack

• can only tell if have chiral center

1. what is the reaction scheme?

2. find the products

3. is the reverse reaction possible?

1. SN2

2. picture

3. No b/c OMe is NOT a good LG

1. what is the reaction scheme?

2. find the major product

3. draw the rxn coordinate diagram

E2

1. what is the reaction scheme?

2. find the products (hint: convert to NP)

E2

1. what is the reaction scheme?

2. find the products

E2

1. what is the reaction scheme?

2. find the products

E2

1. find all of the products (hint: SN2 + E2)

1. find the product

2. what if there were excess NaCN?

1. what is the reaction scheme?

2. find the major product

1. what is the reaction scheme?

2. find the major product

which molecule is the more stable and why?

1. find the product of each reaction

2. draw the rxn coordinate diagram

perform a ring expansion on this molecule

perform a 1,2-hydride shift

perform a 1,2-methyl shift on this molecule

1. what is the reaction scheme?

2. find the product (show your work)

3. is this reaction always racemic?

1. SN1

2. pic

3. No

1. what is the reaction scheme?

2. find the product (show your work)

E1

1. draw the rxn coordinate diagram for this reaction

1. draw the rxn coordinate diagram for this reaction

1. predict the major organic product(s)

2. specify stereochemistry if applicable

3. draw the rxn coordinate diagram

1. predict the major organic product(s)

2. specify stereochemistry if applicable

1. perform this intramolecular reaction

2. is this the same molecule?

1. pic

2. yes

1. perform this intramolecular reaction

2. is this the same molecule?

1. pic

2. yes

1. what is the reaction scheme?

2. find the major product

draw all possible products (major & minor)

1. label what happened in between each step

2. draw the product

1. fill in the major organic product

2. assign R/S

3. which is a faster solvent and why?: DMSO vs H₂O

compare which is faster and why?

1. predict the product(s)

2. draw the mechanism

3. draw the rxn coordinate diagram

1. how did this reaction take place?

2. fill in what reacted with the molecule (hint: more than 1 step)