Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2020 Jan 9;13(1):131-135.
doi: 10.1002/cssc.201902346. Epub 2019 Nov 27.

N-Heterocyclic Carbene Acyl Anion Organocatalysis by Ball-Milling

William I Nicholson  1 , Alex C Seastram  1 , Saqib A Iqbal  1 , Benjamin G Reed-Berendt  1 , Louis C Morrill  1 , Duncan L Browne  1
Affiliations

N-Heterocyclic Carbene Acyl Anion Organocatalysis by Ball-Milling

William I Nicholson et al. ChemSusChem. .

Abstract

The ability to conduct N-heterocyclic carbene-catalysed acyl anion chemistry under ball-milling conditions is reported for the first time. This process has been exemplified through applications to intermolecular-benzoin, intramolecular-benzoin, intermolecular-Stetter and intramolecular-Stetter reactions including asymmetric examples and demonstrates that this mode of mechanistically complex organocatalytic reaction can operate under solvent-minimised conditions.

Keywords: N-heterocyclic carbenes; acyl anion; ball milling; mechanochemistry; organocatalysis.

PubMed Disclaimer

Conflict of interest statement

The authors declare no conflict of interest

Figures

Figure 1
Figure 1
(a) Some areas of organocatalysis; (b) example activation modes of NHC catalysis; (c) this work: NHC acyl anion organocatalysis under ball‐milling conditions.
Scheme 1
Scheme 1
NHC‐catalysed benzoin reaction under milling conditions.
Scheme 2
Scheme 2
NHC‐catalysed Stetter reaction under milling conditions.
Scheme 3
Scheme 3
Overview of asymmetric NHC‐mediated acyl anion chemistry under milling conditions.
See this image and copyright information in PMC

References

    1. For the IUPAC Gold Book definition of mechanochemistry see: https://goldbook.iupac.org/terms/view/MT07141 or 10.1351/goldbook.MT07141. - DOI
    1. For selected reviews in the area of mechanochemistry see:
    1. Howard J. L., Cao Q., Browne D. L., Chem. Sci. 2018, 9, 3080–3094; - PMC - PubMed
    1. Andersen J., Mack J., Green Chem. 2018, 20, 1435–1443;
    1. Do J.-L., Friščić T., ACS Cent. Sci. 2017, 3, 13–19; - PMC - PubMed

LinkOut - more resources