Pd(II)-catalyzed atroposelective and enantioselective C−H olefination of [n]metacyclophanes

Abstract

A Pd(II)-catalyzed C–H olefination strategy has been established for the enantioselective synthesis of [n]metacyclophanes. The method demonstrates excellent functional group tolerance across a series of olefins and metacyclophane precursors with varying ansa-chain lengths, achieving high stereocontrol through kinetic or dynamic kinetic resolution. Racemization experiments were conducted to investigate the relationship between molecular structure and conformational stability. Furthermore, the synthetic utility of this approach was demonstrated through gram-scale synthesis and the application of a resulting bifunctional thiourea catalyst in asymmetric Michael additions, highlighting its potential in asymmetric synthesis.

Keywords

Metacyclophanes / C–H olefination / asymmetric catalysis / palladium

Authors contribution

Tang Q, Zhao C: Conceptualization, writing-original draft, writing-review & editing, data curation, formal analysis. Yan XE, Li J, Dong Z, Zhai H: Methodology, investigation, data curation, formal analysis.

Conflicts of interest

The authors declare 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 and materials could be obtained from the corresponding author upon request.

Funding

This research was supported by the National Natural Science Foundation of China Foundation of China (Grant No. 22571022).

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