AI Article Synopsis
- Phosphines can enhance the organocatalytic β-boration reaction of α,β-unsaturated carbonyl compounds, reducing the need for traditional Brönsted bases.
- The interaction between phosphines and the substrate leads to the formation of a zwitterionic phosphonium enolate.
- This enolate can interact with methanol and B(2)pin(2) to create an ion pair that is crucial for the catalytic process.
Article Abstract
The use of phosphines to assist the organocatalytic β-boration reaction of α,β-unsaturated carbonyl compounds has been demonstrated with a selected number of substrates. The new method eludes the use of Brönsted bases to promote the catalytic active species and PR(3) becomes essential to interact with the substrate resulting in the formation of a zwitterionic phosphonium enolate. This species can further deprotonate MeOH when B(2)pin(2) is present forming eventually the ion pair [α-(H),β-(PR(3))-ketone](+)[B(2)pin(2)·MeO](-) that is responsible for the catalysis.
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| http://dx.doi.org/10.1039/c2ob26899j | DOI Listing |
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