Epoxidation Practice Problems

An optically active epoxide is produced when (E)-1,2-dicyclopentylethene is epoxidized in an enantioselective manner using the Jacobsen catalyst. However, the product is optically inactive when the same conditions are utilized using (Z)-1,2-dicyclopentylethene as a substrate. Elucidate this observation.

Draw the product(s) formed when the given alkene undergoes a reaction with  mCPBA.

Draw the product(s) formed when the given molecule reacts with mCPBA, followed by sulfuric acid.

Draw the product(s) formed when the given compound reacts with  m-CPBA.

Draw the product(s) formed when the given alkene molecule undergoes a reaction with (1) mCPBA and then with (2) H₂SO₄/H₂O.

Determine the reaction's atom economy below and describe the fate of the remaining percentage of material not utilized in the major product.

Draw the products of the reaction of the given molecule with mCPBA.

Indicate the stereochemistry, and draw both enantiomers if the product is a racemic mixture.

Even though the epoxidation reaction is stereospecific, the formation of an epoxide will lead to a mixture of enantiomers while producing a chiral compound.

Why does the reaction form a racemic mixture of products?

Despite the fact that the reaction is stereospecific, the formation of an epoxide will lead to a mixture of enantiomers while producing the chiral molecule.

How can a reaction be stereospecific and still yield two enantiomers?

Rank the following alkenes with respect to relative reactivity with m-CPBA, 1 being the most reactive and 5 being the least.

To gain insight into concerted reactions, one can conceptualize them as stepwise reactions where all steps, except the slowest one, possess exceedingly small activation energies. Illustrate the hypothetical stepwise mechanism by presenting a reaction coordinate diagram for the following example.

To gain insight into concerted reactions, one can conceptualize them as stepwise reactions where all steps, except the slowest one, possess exceedingly small activation energies. Illustrate the actual concerted mechanism of the reaction through a reaction coordinate diagram.

An optically active epoxide is produced when (E)-1,2-dicyclopentylethene is epoxidized in an enantioselective manner using the Jacobsen catalyst. However, the result is optically inactive when the same conditions are utilized using (Z)-1,2-dicyclopentylethene as the substrate. Elucidate this finding.

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Provide two different pathways to carry out the following reaction.

For the reaction of 3-ethyl-2-methylpent-2-ene with m-CPBA (meta-chloroperoxybenzoic acid), predict the major product.

Illustrate the product(s) that will be formed in the reactions of cis-3-hexene and trans-3-hexene with a peroxyacid. State which stereoisomers are produced, if applicable.

Provide the products for the epoxidation reactions of the following alkenes through m-chloroperoxybenzoic acid. Include stereochemistry where appropriate.

a. cis-but-2-ene
b. trans-but-2-ene

Provide the products for the epoxidation reactions of the following alkenes through m-chloroperoxybenzoic acid. Include stereochemistry where appropriate.

a. cis-cyclononene
b. trans-cyclononene

Provide the structure of the major product in the epoxidation reaction given below.

cis-but-2-ene + m-CPBA in chloroform