Ylide
| Formula / Notation | R₂S⁺-CH₂⁻ or R₃P⁺-CH₂⁻ |
|---|---|
| Also Known As | Phosphorus ylide, sulfur ylide, Wittig reagent, zwitterionic reagent |
What is Ylide?
A neutral dipolar molecule containing formal positive and negative charges on adjacent atoms, neither of which carries a hydrogen atom. Phosphorus ylides (used in Wittig reactions) and sulfonium ylides are important reagents in organic synthesis for making alkenes from carbonyl compounds.
Formula & Notation
Other Names / Synonyms: Phosphorus ylide, sulfur ylide, Wittig reagent, zwitterionic reagent
Properties & Characteristics
Uses & Applications
Safety Information
Always consult the SDS/MSDS before handling any chemical. This information is for educational purposes only.
Key Facts
Frequently Asked Questions
A neutral dipolar molecule containing formal positive and negative charges on adjacent atoms, neither of which carries a hydrogen atom. Phosphorus ylides (used in Wittig reactions) and sulfonium ylides are important reagents in organic synthesis for making alkenes from carbonyl compounds.
Phosphorus ylides are key reagents in the Wittig reaction widely used in organic synthesis to make alkenes with precise double bond position. Sulfur ylides are used to prepare cyclopropanes and epoxides. Ylide chemistry is important in natural product and pharmaceutical synthesis.
Ylide reagents (phosphorus ylides, sulfur ylides) may be reactive and moisture-sensitive. Some are prepared using strongly basic conditions (n-BuLi) requiring inert atmosphere techniques. Triphenylphosphine oxide by-product from Wittig reaction is a waste issue.
The formula or notation for Ylide is: R₂S⁺-CH₂⁻ or R₃P⁺-CH₂⁻