AI Article Synopsis
- Researchers developed a new linked bis-thiourea catalyst that shows improved activity compared to single-component (monomeric) versions in a specific type of reaction called enantioselective anion-abstraction.
- The design leverages mechanistic insights to ensure two thiourea units work together effectively without forming unproductive aggregates.
- This innovative catalyst allows for much lower usage rates (as low as 0.05 mol %) and offers deeper understanding of the anion-binding mechanisms involved in the catalysis process.
Article Abstract
We describe the rational design of a linked, bis-thiourea catalyst with enhanced activity relative to monomeric analogues in a representative enantioselective anion-abstraction reaction. Mechanistic insights guide development of this linking strategy to favor substrate activation though the intramolecular cooperation of two thiourea subunits while avoiding nonproductive aggregation. The resulting catalyst platform overcomes many of the practical limitations that have plagued hydrogen-bond-donor catalysis and enables use of catalyst loadings as low as 0.05 mol %. Computational analyses of possible anion-binding modes provide detailed insight into the precise mechanism of anion-abstraction catalysis with this pseudo-dimeric thiourea.
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| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5380606 | PMC |
| http://dx.doi.org/10.1021/jacs.6b09205 | DOI Listing |
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