Unprecedented Reactions Mediated by Samarium: An Approach to Nonstabilized Carbonyl Ylides

摘要

Samarium is widely applied to organic synthesis in the formation of carbon—carbon bonds and the transformation of a variety of functionalities with high selectivities. In these reactions, carbanions and radicals are thought to be involved as transient active species. We report herein the generation of novel active species, nonstabilized carbonyl ylides from iodomethyl silyl ethers mediated by samarium, otherwise inaccessible, and their [3 + 2] cycloadditions to a variety of unsaturated compounds such as aldehydes, alkenes, allenes, and alkynes (Scheme 1).