ylide

chemical compound

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Last updated

July 15, 2026

Quick Summary

A ylide is a neutral molecule with a negatively charged atom (typically carbon) directly bonded to a positively charged atom (typically a heteroatom like sulfur or phosphorus). This arrangement creates a zwitterionic structure.1

Sulfur ylides are a type of ylide where sulfur carries the positive charge. They are formed when sulfonium or oxosulfonium salts react with a base, causing a proton to be lost from a carbon atom adjacent to the positively charged sulfur. These ylides are valuable in organic synthesis, particularly for creating epoxides.1

The term "-ylidene" is a suffix used in chemistry to denote a bivalent radical derived from a hydrocarbon by removing two hydrogen atoms from the same carbon atom or by removing the oxygen atom from an aldehyde.2

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Georg Wittig
…of organic phosphorus compounds called ylides that mediate a particular type of reaction that became known as the Wittig reaction. This reaction proved of great value in the synthesis of complex organic compounds such as vitamins A and D₂, prostaglandins, and steroids.
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…of organic phosphorus compounds called ylides that mediate a particular type of reaction that became known as the Wittig reaction. This reaction proved of great value in the synthesis of complex organic compounds such as vitamins A and D₂, prostaglandins, and steroids.
Read More