Chemical Behaviour of a Prototype Boryl(phosphino)carbene

Florie Lavigne (1) , Eddy Maerten (1) , Gilles Alcaraz (2) , Nathalie Saffon-Merceron (3) , Antoine Baceiredo (1)

1 LHFA - Laboratoire Hétérochimie Fondamentale et Appliquée
2 LCC - Laboratoire de chimie de coordination
3 ICT - Institut de Chimie de Toulouse

We recently disclosed the synthesis of a novel "push-pull" boryl(phosphino)carbene. To determine the influence of this substitution pattern on the chemical behaviour, a study into the reactivity of the prototype (1) of this new family of B(sp 2)-substituted phosphinocarbenes was undertaken. Carbene 1 exhibits one of the most common intramolecular rearrangements of singlet carbenes, involving a 1,2-mesityl shift, and typical [2+1] cycloaddition reactions with electron-poor acrylonitrile. A pronounced a,b-ambiphilic character was also shown by the reaction of 1 with benzaldehyde, leading to phosphorylalkene 4. Due to its specific electronic properties, carbene 1 also exhibits unprecedented reactivity with chloroacrylonitrile, enabling the formation of bicyclo[1.1.0]phosphetanium salt 6 and borylcyclopropene 9, which have been fully characterised by NMR spectroscopy and X-ray crystallography.

Domaines: Chimie organique

Florie Lavigne, Eddy Maerten, Gilles Alcaraz, Nathalie Saffon-Merceron, Antoine Baceiredo. Chemical Behaviour of a Prototype Boryl(phosphino)carbene. Chemistry - A European Journal, 2013, 20 (1), pp.297 - 303. ⟨10.1002/chem.201303039⟩. ⟨hal-03412871⟩