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Preparation and Use of Carbonyl-decorated Carbenes in the Activation of White Phosphorus
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Chemical behaviour of a prototype boryl(phosphino)carbene
Florie Lavigne1, Eddy Maerten, Gilles Alcaraz
1Université de Toulouse, UPS, and CNRS, LHFA UMR 5069, 31062 Toulouse Cedex 9 (France), Fax: (+33) 561558204.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|November 29, 2013
Summary
This study explores the reactivity of a novel boryl(phosphino)carbene. Its unique electronic properties enable common carbene rearrangements and cycloadditions, along with unprecedented reactions forming new cyclic compounds.
Area of Science:
- Organometallic Chemistry
- Carbene Chemistry
- Boron Chemistry
Background:
- Novel boryl(phosphino)carbene synthesis reported.
- Understanding the influence of B(sp(2))-substitution on carbene reactivity is crucial.
Purpose of the Study:
- Investigate the chemical behavior and reactivity of a prototype boryl(phosphino)carbene.
- Determine the impact of the unique push-pull electronic substitution pattern on carbene reactions.
Main Methods:
- Reactions of the boryl(phosphino)carbene with various substrates including acrylonitrile and benzaldehyde.
- Characterization of reaction products using Nuclear Magnetic Resonance (NMR) spectroscopy and X-ray crystallography.
Main Results:
- The carbene undergoes typical intramolecular 1,2-mesityl shifts and [2+1] cycloadditions with acrylonitrile.
- Demonstrated pronounced alpha,beta-ambiphilic character in reactions with benzaldehyde, yielding phosphorylalkene.
- Exhibited unprecedented reactivity with chloroacrylonitrile, forming bicyclo[1.1.0]phosphetanium salt and borylcyclopropene.
Conclusions:
- The B(sp(2))-substitution pattern significantly influences carbene reactivity.
- The novel boryl(phosphino)carbene displays a versatile reaction profile, including known carbene pathways and unique transformations.
- The study expands the scope of carbene chemistry and provides insights into the behavior of electronically distinct carbenes.
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