Exploring Heterotropones and Examining Their Propensity to Undergo [4 + 2] Cycloadditions

Barløse, Casper Larsen; Faghtmann, Jonas; Kaasik, Mikk; Mastroddi, Roberta; Jørgensen, Karl Anker

doi:10.1021/acs.orglett.3c04080

Org. Lett.

2024

DOI: 10.1021/acs.orglett.3c04080

|View full text |Cite

Exploring Heterotropones and Examining Their Propensity to Undergo [4 + 2] Cycloadditions

Casper Larsen Barløse,

Jonas Faghtmann,

Mikk Kaasik

et al.

Abstract: An efficient strategy to obtain a broad array of chiral and achiral heterotropones and their corresponding [4 + 2] cycloadducts is disclosed. This strategy enables access to unique heterotropones and intricate bicyclic structures in high yields and diastereoselectivities through a simple procedure and from easily accessible starting materials.

Help me understand this report

Search citation statements

Order By: Relevance

Paper Sections

Select...

Citation Types

Supporting

Mentioning

Contrasting

Year Published

2024

2025

Publication Types

Select...

Article3

Relationship

Self Cite0

Independent3

Authors

Journals

Cited by 3 publications

References 43 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

Site-Selective Gold-Catalyzed Alkylation of α-Aminotropones with Allenes

Gallorini,

Kiriakidi,

Bellini

et al. 2024

Org. Lett.

View full text Add to dashboard Cite

The site-selective alkylation of α-aminotropones is effectively realized via gold(I)-catalyzed electrophilic activation of allenamides and allenyl ethers, yielding up to 85% in 30 examples. A dedicated and combined spectroscopic and computational investigation accounts for both chemo-and regioselective profiles of the protocol. New opportunities in the chemical space of tropone/tropolone derivatives are identified.

show abstract

Site-Selective Gold-Catalyzed Alkylation of α-Aminotropones with Allenes

Gallorini,

Kiriakidi,

Bellini

et al. 2024

Org. Lett.

View full text Add to dashboard Cite

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

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

Recent advances in the transformation of maleimides via annulation

Aslam,

Akhtar,

Lim

et al. 2025

Org. Biomol. Chem.

View full text Add to dashboard Cite

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.

Exploring Heterotropones and Examining Their Propensity to Undergo [4 + 2] Cycloadditions

Cited by 3 publications

References 43 publications

Site-Selective Gold-Catalyzed Alkylation of α-Aminotropones with Allenes

Site-Selective Gold-Catalyzed Alkylation of α-Aminotropones with Allenes

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

Recent advances in the transformation of maleimides via annulation

Contact Info

Product

Resources

About