Silylmethyl-substituted cyclopropyl and other strained ring systems: cycloaddition with dipolarophiles

Small ring compounds represent a class of versatile building blocks in organic synthesis. Three- and four-membered ring carbo- and heterocycles are regarded as unique functional groups. Lewis acid-assisted cycloaddition of cyclopropanes, aziridines and azetidines substituted by vicinal electron-donor and electron-acceptor groups takes place in a regio- and stereocontrolled fashion. Trialkylsilylmethyl is an interesting donor substituent. In this feature article, we provide an overview of the cycloaddition of different dipolarophiles to silylmethyl-substituted small ring compounds and discuss their possible applications in synthesis.