Carbene-stabilized phosphenium oxides and sulfides.
Carbene→chalcogenophosphenium adducts, which correspond to an intermolecular stabilization mode of the so far elusive, free oxo- and thiooxophosphenium species [R(2)P(+) = X] (X = O, S) by imidazolylidene (NHC) and diaminocyclopropenylidene (BAC) donors, have been isolated and fully characterized. The dative character of the R(2)C:→P(+)(X)Ph(2) bond was confirmed experimentally by nucleophilic displacement of the carbene donor with a chloride ion and by an exchange reaction of the NHC ligand of the NHC:→P(+)(O)Ph(2) adduct with an independently prepared BAC ligand, thereby giving the BAC:→P(+)(O)Ph(2) adduct. This dative character was further characterized by the DFT-calculated preference of carbene→chalcogenophosphenium systems for a heterolytic dissociation mode over a homolytic one.
CNRS, LCC (Laboratoire de Chimie de Coordination), 205 route de Narbonne, F-31077 Toulouse, France.
Carine
C
Maaliki
Christine
C
Lepetit
Carine
C
Duhayon
Yves
Y
Canac
Remi
R
Chauvin