The Peterson Olefination Reaction

Abstract

The Peterson olefination reaction provides a useful method for the preparation of alkenes from α-silyl carbanions and carbonyl compounds. As alkenes hold a pivotal role in synthetic methodology for the introduction of vicinal functionality, particularly in a stereoselective manner, the Peterson reaction is increasing in importance in the reaction repertoire. This chapter discusses the reaction and its advantages over comparable methods such as the Wittig reaction. Although elimination of β-silylalkoxides, was noted in 1947, it was not until Peterson described the preparation of functionalized alkenes from α-silyl carbanions in 1968 that the full potential of the reaction became apparent. Alkenes are usually only isolated directly from the condensation when an anion-stabilizing group is present in the carbanion; if not, the β-hydroxysilane is formed. Many examples of the formation of alkenes from β-hydroxysilanes are cited in the literature. These eliminations are discussed in this chapter, although they strictly should not be called Peterson olefination reactions. However, the “common” organic reactions of β-hydroxysilanes which follow the usual pathways—such as the thermolytic elimination of esters derived from those alcohols—are omitted. The central nature of the Peterson reaction to organosilicon chemistry has led all reviews in this area to discuss the subject to some extent. In addition, the reaction itself has been reviewed previously. Keywords: Peterson olefination; mechanisms; scope; limitations; diastereoselective synthesis; hydroxysilanes; silyl carbions; carbonyl groups; unsaturation; silyl-nitrogen compounds; silyl-sulfur compounds; silyl selenium compounds; functional groups; carbonyl compounds; electrophiles; Homo-Peterson reaction; Brook rearrangement; Sila-Pummerer rearrangements; Wittig reaction; experimental procedures