Experiment 6- Epoxidation Reactions Flashcards
What type of molecules are epoxides?
A type of ether.
Why are so many epoxides studied?
Due to their anti-cancer affects.
What is an example of a compound that exhibits properties of interest in epoxides?
Capsaicin, the chemical in peppers that’s responsible for the burning sensation. Capsaicin’s alkene gets converted to an epoxide, exhibiting many anti-cancer properties.
Define Chemoselectivity
The preferred chemical outcome with one functional group over another (one functional group selectively reacts more than the others)
What is mCPBA used for?
For the synthesis of epoxides. It transferred one of its oxygens to ketones and alkenes readily.
How can oxygen-oxygen bonds be characterized?
Weak, they can easily be broken.
How do you know if something has been oxidized?
If there has been an increase in the # of oxygens in the product.
What is the byproduct of epoxidation reactions?
MCBA, containing one less oxygen compared to mCPBA.
MCPBA reacts best with electron rich alkenes. To epoxidize electron-poor alkenes, what is done? What is the main difference between this and electron-rich alkenes.
A combination of NaOH and H2O2 are used. With electron poor-alkenes, the reaction occurs in a stepwise mechanism through a peroxy intermediate.
What is the main purpose of NaOH with epoxidation of electron-poor alkenes?
It is used as a catalyst. Regeneration occurs on the product side.
With electron-poor alkene epoxidation, the alkene is the _____ and the hydrogen peroxide is the _____.
Electrophile-Nucleophile.
What happens with mCPBA and H2O2 oxidizing ketones?
An oxygen gets bonded between the carbon and the substituent. This is called the Baeyer-Villiger oxidation reaction.
