Diradical Character of Cyclic Allenes Enables Their Thermal (2 + 2) Cycloadditions.

Noah W Gilbertson, Allison T Hands, Jacob P Sorrentino, K N Houk, Neil K Garg

Abstract read

In one paragraph

Article in Journal of the American Chemical Society, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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0citing papers in PubMed

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1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

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3 · Its place in the literature

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0 citing papers in PubMed.

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4 · The record

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PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

5 authors.

Noah W GilbertsonDepartment of Chemistry and Biochemistry, University of California, Los Angeles, California90095, United States.

Allison T HandsDepartment of Chemistry and Biochemistry, University of California, Los Angeles, California90095, United States.

Jacob P SorrentinoDepartment of Chemistry and Biochemistry, University of California, Los Angeles, California90095, United States.

K N HoukDepartment of Chemistry and Biochemistry, University of California, Los Angeles, California90095, United States.ORCID 0000-0002-8387-5261

Neil K GargDepartment of Chemistry and Biochemistry, University of California, Los Angeles, California90095, United States.ORCID 0000-0002-7793-2629

Funding

Exploiting Unconventional Building Blocks in Chemical SynthesisR35GM139593 · NIGMS · UNIVERSITY OF CALIFORNIA LOS ANGELES · PI Neil K. Garg · 2021 to 2026

$4.0M

NMR Console and Prodigy CryoProbeS10OD028644 · OD · UNIVERSITY OF CALIFORNIA LOS ANGELES · PI GARG, NEIL K · 2021 to 2021

$600k

Time-of-Flight Mass Spectrometer for Synthesis Supporting Biomedical ResearchS10RR025631 · NCRR · UNIVERSITY OF CALIFORNIA LOS ANGELES · PI HOUK, KENDALL N · 2009 to 2009

$328k

Division of Chemistry CHE-1048804Division of Chemistry CHE-2452867Division of Graduate Education DGE-2034835National Institutes of Health (NIH) S10OD028644National Institutes of Health (NIH) S10RR025631NCRR NIH HHS S10 RR025631NIGMS NIH HHS R35 GM139593NIH HHS S10 OD028644

6 · The paper itself

Abstract

(2 + 2) Cycloadditions are a versatile transformation often employed in the synthesis of cyclobutanes. Such cycloadditions usually require the use of light or another synthetic workaround, given that thermal (2 + 2) cycloadditions are orbital symmetry-forbidden for unstrained all-suprafacial transition states. A unique type of (2 + 2) cycloaddition involves transient strained cyclic allenes, which proceed readily at ambient temperature without external stimuli. In the present study, computations and experiments show that the feasibility of these cycloadditions is tied to the inherent diradical character of the cyclic allenes. Moreover, comparative stereochemical transfer experiments for Diels-Alder and (2 + 2) cycloadditions are consistent with strained cyclic allenes having both closed- and open-shell character, thus rendering them diradicaloids. This study is expected to prompt the further strategic use of diradicaloids for the assembly of complex scaffolds.

Identifiers

PMID42617096

DOI10.1021/jacs.6c09105

PMCPMC13527721

What OpenQuestion holds

Textmetadata

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.