Synthesis of Novel Steroid Backbones via Photoinduced Electron Transfer Initiated Domino Cyclizations of Silyl Enol Ethers

Abstract

Photoinduced electron transfer was used to activate silyl enol ethers. The generated radical cations of specifically designed precursors undergo ring closure reactions to yield novel steroid compounds. These domino reactions proceed with high stereoselectivity. The synthesis of the complex silyl enol ethers, the stereo­selective domino cyclization process and the assignment of stereochemistry of the novel steroid compounds is presented.

Key words

domino reactions - cyclizations - stereoselectivity - electron transfer - steroids

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