Prilezhaev

Prilezhaev refers to Nikolai Stepanovich Prilezhaev, a Russian chemist best known for describing what is now called the Prilezhaev reaction, an early foundational transformation in epoxidation chemistry. In the Prilezhaev epoxidation, alkenes are converted to epoxides by treatment with a peracid, such as performic acid, peracids generated in situ, or meta-chloroperoxybenzoic acid (mCPBA). The reaction typically produces the epoxide and a carboxylic acid as a byproduct, under relatively mild conditions.

The reaction is valued for its stereospecificity, often proceeding with syn addition across the carbon–carbon double bond. It is applicable to a broad range of alkenes, providing a straightforward route to epoxides, which are versatile intermediates in organic synthesis. Substrate scope can vary with the nature of the alkene and the chosen peracid; electron-rich alkenes react readily, while highly electron-poor substrates may require adjustments.

Mechanistically, the process is understood as a concerted transfer of an oxygen atom from the peracid to the double bond, yielding the three-membered epoxide ring and the corresponding carboxylic acid. The method remains a standard teaching example of peracid epoxidation and is frequently used in laboratory settings for the preparation of epoxides, especially when stereochemical outcomes are important.

Significance: Prilezhaev’s work laid early foundations for epoxidation chemistry and influenced subsequent developments in epoxide synthesis, including later asymmetric and catalytic methods. The term Prilezhaev epoxidation is synonymous with peracid-based epoxidations in many texts.