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Updated: May 13, 2025

Synthesis of Hypervalent Iodonium Alkynyl Triflates for the Application of Generating Cyanocarbenes
Published on: September 8, 2013
Iron-catalyzed sequential hydrosilylation
Xue Wang1, Jiajin Zhao1, Dongyang Wang2
1Center of Chemistry for Frontier Technologies, Department of Chemistry, Zhejiang University, Hangzhou, China.
Abstract:
Highly regio-, diastereo- and enantioselective iron-catalyzed sequential hydrosilylation of o-alk-n-enyl-phenyl silanes with alkynes is reported for various 5-, 6-, and 7-membered benzosilacycles in 60-94% yields with up to 95:5 rr, 95:5 dr, and 99% ee. Chiral fully carbon-substituted silicon-stereogenic benzosilacycles could also be obtained via triple hydrosilylation reactions. The unique electronic effect of ligands is observed while adjusting the regioselectivity and enantioselectivity in hydrosilylation reactions. A possible mechanism has been proposed by variable time normalization analysis (VTNA) and H/D exchange experiment.
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