Iridium(I)-catalyzed enantioselective five- and six-membered C–H silylation of ferrocenes

Abstract

We report the first Ir(I)-catalyzed enantioselective intramolecular C–H silylation of ferrocenes for the efficient construction of planar-chiral 5- and 6-membered ferrocenyl silacycles. This method overcomes key limitations of existing Rh(I)-based systems, offering superior reactivity, enhanced cost-effectiveness, and broader substrate scope, including challenging C3- and C6-substituted derivatives, as well as excellent enantiocontrol under mild conditions without requiring exogenous H₂ acceptors. The utility of the obtained planar-chiral scaffolds is preliminarily demonstrated through the synthesis of novel monophosphine ligands, which exhibit promising activity in asymmetric catalysis.

Keywords

Ferrocenes / silylation / enantioselectivity / planar chirality

Authors contribution

Gao F, Sun, H, Zhang, H: Investigation, writing-review & editing. Zhao D: Conceptualization, writing-original draft, writing-review & editing.

Conflicts of interest

Dongbing Zhao is an Editorial Board Member of Chiral Chemistry . Other authors declared that there are no conflicts of interest.

Ethical approval

Not applicable.

Consent to participate

Not applicable.

Consent for publication

Not applicable.

Availability of data and materials

The data that support the findings of this study are available from the corresponding author upon reasonable request.

Funding

We are grateful for the financial support from the National Natural Science Foundation of China (Grant Nos. 22221002 and 22371132), the Natural Science Foundation of Tianjin (23JCJQJC00130), the “Frontiers Science Center for New Organic Matter”, Nankai University (Grant No. 63181206), Fundamental and Interdisciplinary Disciplines Breakthrough Plan of the Ministry of Education of China (Grant No. JYB2025XDXM410).

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