Application of Silicon-based Methodologies for the Synthesis of Functionalized Mono- and Bisphosphonic Acids

The aim of this article is to present an overview of new and useful silicon-based methodologies valuable for the selective construction of highly functionalized mono- and bisphosphonic acids of high synthetic and biological importance. The reactions of trimethylsilyl phosphites with alkyl halides, carbonyl compounds and imines are presented as a platform for developing new approaches to biologically active hydroxy-, amino-, fluoro-substituted mono- and bisphosphonates. The second part of the review consists of a presentation of methodology involving the fluoride-induced formation of α-phosphonylated carbanions from 1-trimethylsilyl methylphosphonates. The third part of the review describes the methodology employing silylated phosphonate carbanions. Application of trimethylsilyl as protecting group is discussed in separate section.