Substrate-Controlled [8 + 3] Cycloaddition of Tropsulfimides and Tropones with Zwitterionic Allenyl Palladium Species Derived from Vinylidenecyclopropane-diesters

Long, Yong-Jie; Shen, Jia-Hao; Wei, Yin; Shi, Min

doi:10.1021/acs.joc.4c01579

J. Org. Chem.

2024

DOI: 10.1021/acs.joc.4c01579

|View full text |Cite

Substrate-Controlled [8 + 3] Cycloaddition of Tropsulfimides and Tropones with Zwitterionic Allenyl Palladium Species Derived from Vinylidenecyclopropane-diesters

Yong-Jie Long,

Jia-Hao Shen,

Yin Wei

et al.

Abstract: A palladium-catalyzed regioselective [8 + 3] cycloaddition of tropsulfimides and tropones with vinylidenecyclopropane-diesters (VDCP-diesters) has been disclosed in this paper, affording decahydro-1H-cyclohepta[b]pyridine derivatives bearing an allene moiety or decahydro-1H-cyclohepta[b]pyran derivatives having a conjugated diene unit in moderate to good yields. The reactions proceed through a zwitterionic allenyl palladium species derived from VDCP-diesters. The substrate scopes have been investigated and the… Show more

Help me understand this report

Search citation statements

Order By: Relevance

Paper Sections

Select...

Citation Types

Supporting

Mentioning

Contrasting

Year Published

2024

Publication Types

Select...

Article2

Relationship

Self Cite0

Independent2

Authors

Journals

Cited by 2 publications

References 73 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

Mechanistic Investigation of the Pseudo-Halogen Effect in Enantioselective Aminocatalyzed [6 + 4] and [10 + 6] Cycloadditions: Enabling Unique Favorskii-Like Rearrangements

Barløse,

Bitsch,

Faghtmann

et al. 2024

J. Am. Chem. Soc.

View full text Add to dashboard Cite

A mechanistic investigation into the novel combination of the pseudo-halogen effect with enantioselective aminocatalysis unravels the mechanistic intricacies of [6 + 4] and [10 + 6] higher-order cycloadditions and the succeeding new Favorskii-like rearrangements. By introducing the OTf-group into the tropone framework, it can serve both as an activator for the cycloaddition and as a proficient leaving group within the corresponding cycloadduct, thus enabling unprecedented ring-contracting Favorskii-like rearrangements. Integrating the -OTf group creates an electron-deficient 6π-component leveraging the pseudo-halogen effect by enhancing the polarization and introducing new strategic interaction points. This modification complements electron-rich 4π-and 10π-components from amino-activated 2,4-dienals or indene-carbaldehydes. A comprehensive DFT investigation supported by experimental results demonstrates that the [6 + 4] system proceeds through a rate-limiting stepwise exo-cycloaddition leading to a cycloadduct initially in a boat-conformation, subsequently transitioning to the more stable chair-conformation. The change in conformation ensures an S N 1-like expulsion of the -OTf group, generating a stable carbocation bridgehead primed for a novel Favorskii-like seven-to-six ring-contracting rearrangement, resulting in the experimentally observed product. As proof-of-concept for the cycloaddition/Favorskii-like rearrangement, it is demonstrated that this approach can be extended to an unprecedented [10 + 6] cycloaddition. In contrast to the [6 + 4] system, the [10 + 6] system distinguishes itself with a concerted S N 1-like/Favorskii-like six-to-five ring-contracting rearrangement, representing the rate-limiting step. This novel concept results in the experimental isolation of structurally complex products in high peri-, diastereo-, and enantioselectivity with moderate yield. These findings demonstrate the pseudo-halogen effect's multifaceted role in promoting and enabling novel reactivity.

show abstract

Mechanistic Investigation of the Pseudo-Halogen Effect in Enantioselective Aminocatalyzed [6 + 4] and [10 + 6] Cycloadditions: Enabling Unique Favorskii-Like Rearrangements

Barløse,

Bitsch,

Faghtmann

et al. 2024

J. Am. Chem. Soc.

View full text Add to dashboard Cite

show abstract

Theoretical Studies on the Reaction Mechanism for the Cycloaddition of Zwitterionic π-Allenyl Palladium Species: Substrate-Controlled Isomerization

Long,

Shen,

Shi

et al. 2024

Molecules

View full text Add to dashboard Cite

Zwitterionic π-allenyl palladium species are newly developed intermediates. A substrate-controlled step existed in the cycloaddition of zwitterionic π-allenyl palladium species with tropsulfimides or tropones. With the assistance of previously experimental studies, zwitterionic allenyl/propargyl palladium species was provenly found by HRMS. Further DFT calculation studies show that zwitterionic π-allenyl palladium species are generated through the oxidative addition of Pd(0), which can be promoted by Lewis acid like Yb(OTf)3, and the cycloaddition more likely undergoes through an outer sphere nucleophilic attack. The isomerization is caused by the difference of dissociation energy between the cycloaddition intermediation of tropsulfimides and tropones, forming the substrate-controlled specificity.

show abstract

scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.

Contact Info

customersupport@researchsolutions.com

10624 S. Eastern Ave., Ste. A-614

Henderson, NV 89052, USA

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.

Blog Terms and Conditions API Terms Privacy Policy Contact Cookie Preferences Do Not Sell or Share My Personal Information

Made with 💙 for researchers

Part of the Research Solutions Family.

Substrate-Controlled [8 + 3] Cycloaddition of Tropsulfimides and Tropones with Zwitterionic Allenyl Palladium Species Derived from Vinylidenecyclopropane-diesters

Cited by 2 publications

References 73 publications

Mechanistic Investigation of the Pseudo-Halogen Effect in Enantioselective Aminocatalyzed [6 + 4] and [10 + 6] Cycloadditions: Enabling Unique Favorskii-Like Rearrangements

Mechanistic Investigation of the Pseudo-Halogen Effect in Enantioselective Aminocatalyzed [6 + 4] and [10 + 6] Cycloadditions: Enabling Unique Favorskii-Like Rearrangements

Theoretical Studies on the Reaction Mechanism for the Cycloaddition of Zwitterionic π-Allenyl Palladium Species: Substrate-Controlled Isomerization

Contact Info

Product

Resources

About