ArticleChemical science2021
Synthesis of aza-quaternary centers
Article in Chemical science, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 7 papers.
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Who cites it
7 citing papers in PubMed, 32 citations in OpenAlex.
- Recent Progress in Catalytic Asymmetric Pictet-Spengler Reaction to Construct 1,1-Disubstituted Scaffolds.Synthesis · 2026Article
- A Ketone-Accepting Pictet-Spenglerase for the Asymmetric Construction of 1,1-Disubstituted Tetrahydro-ß-carboline Alkaloids.Angewandte Chemie (International ed. in English) · 2025Article
- Catalytic enantioselective nitrone cycloadditions enabling collective syntheses of indole alkaloids.Nature communications · 2024Article
- A genetic optimization strategy with generality in asymmetric organocatalysis as a primary target.Chemical science · 2024Article
- Screening for generality in asymmetric catalysis.Nature · 2022Article
- Palladium-Catalyzed Access to Benzocyclobutenone-Derived Ketonitrones via C(spOrganic letters · 2022Article
- Catalytic Enantioselective Pictet-Spengler Reaction of α-Ketoamides Catalyzed by a Single H-Bond Donor Organocatalyst.Angewandte Chemie (International ed. in English) · 2022Article
Corrections and comments
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Authors and funding
3 authors at 1 institution in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Despite the array of advances that have been made in Pictet-Spengler chemistry, particularly as it relates to the synthesis of β-carboline derivatives of both natural and designed origin, the ability to use such reactions to generate aza-quaternary centers remains limited. Herein, we report a simple procedure that enables the synthesis of a variety of such products by harnessing the distinct reactivity profiles of ketonitrones as activated by commercially available acyl chlorides. Notably, the reaction process is mild, fast, and high-yielding (54-97%) for a diverse collection of substrates, including some typically challenging ones, such as indole cores with electron-deficient substituents. In addition, by deploying an acyl bromide in combination with a thiourea promoter, a catalytic, asymmetric version has been established, leading to good levels of enantioselectivity (up to 83% ee) for several ketonitrones. Finally, the resultant N-O bonds within the products can also be functionalized in several unique ways, affording valuable complementarity to existing Pictet-Spengler variants based on the use of imines.
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Registered trials
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.