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Updated: Mar 23, 2026
08:46
Preparation and Reactivity of a Triphosphenium Bromide Salt: A Convenient and Stable Source of PhosphorusI
Published on: November 22, 2016
8.3K
Nitro-redox reactions at a frustrated borane/phosphane Lewis pair
Guo-Qiang Chen1, Gerald Kehr1, Constantin G Daniliuc1
1Organisch-Chemisches Institut der Universität Münster, Corrensstraβe 40, 48149 Münster, Germany. erker@uni-muenster.de.
Dalton Transactions (Cambridge, England : 2003)
|March 24, 2016
Summary
Frustrated Lewis pairs (FLPs) containing phosphorus and boron successfully reduced nitrobenzene and trans-β-nitrostyrene. The resulting intermediates were trapped via allylboration, forming novel seven-membered boron-oxygen-phosphorus compounds.
Area of Science:
- Organoboron Chemistry
- Organophosphorus Chemistry
- Catalysis
Background:
- Frustrated Lewis pairs (FLPs) are reactive species formed from Lewis acids and bases that do not coordinate.
- FLPs have shown promise in activating small molecules and catalyzing various organic transformations.
Purpose of the Study:
- To investigate the reactivity of unsaturated 1,4-phosphorus/boron (P/B) FLPs with nitroaromatic compounds.
- To synthesize and characterize novel organoboron and organophosphorus compounds derived from FLP reactions.
Main Methods:
- Reaction of unsaturated 1,4-P/B-FLPs with nitrobenzene and trans-β-nitrostyrene.
- Trapping of reaction intermediates using allylboration.
- Characterization of products by X-ray diffraction.
Main Results:
- Nitrobenzene was reduced to nitrosobenzene and subsequently trapped by allylboration to yield seven-membered B-O-P compounds.
- The FLP exhibited analogous reactivity with trans-β-nitrostyrene.
- The structures of the resulting compounds were confirmed through X-ray diffraction analysis.
Conclusions:
- Unsaturated 1,4-P/B-FLPs are effective in reducing nitroaromatic compounds.
- Allylboration provides a viable route for trapping reactive intermediates generated by FLPs.
- This study expands the synthetic utility of FLPs in constructing complex organoboron and organophosphorus frameworks.
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