# SmI2/Sm‐Induced Reductive Silacyclization of Alkene/Diene Derivatives Using Dichlorosilanes or 1,2‐Dichlorodisilanes via Reductive Radical‐Polar Crossover

## TL;DR

This paper introduces a new method using samarium reagents to efficiently create silicon-containing cyclic compounds from simple starting materials.

## Contribution

A SmI2/Sm-mediated reductive radical-polar crossover pathway for constructing diverse silacycles is presented.

## Key findings

- The method enables the synthesis of 4–7-membered silacyclic compounds from unsaturated substrates and dichlorosilanes/disilanes.
- Mechanistic studies reveal the involvement of silyl radical intermediates and a reductive radical-polar crossover pathway.
- The approach demonstrates the versatility of Sm reagents in forming multiple Si─C bonds efficiently.

## Abstract

The development of efficient strategies for constructing cyclic organosilicon frameworks is considered of great importance because of their structural diversity and synthetic utility. Herein, we report a SmI2/Sm‐mediated silacyclization of unsaturated organic compounds with readily available dichlorosilanes and ‐disilanes, enabling convenient access to 4−7‐membered silacyclic compounds. Mechanistic investigations indicate that the reaction involves silyl radical intermediates and proceeds via a reductive radical‐polar crossover (RRPCO) pathway. The present findings showcase the broad potential of Sm reagents in Si─C bond formation, providing a versatile strategy for constructing diverse silicon‐containing frameworks.

A SmI2/Sm‐mediated silacyclization unlocks a concise route to 4–7‐membered silacycles from simple unsaturated substrates and dichlorosilanes/disilanes. The complementary functions of samarium reductants trigger a reductive radical–polar crossover, offering a versatile strategy for constructing multiple Si─C bonds efficiently.