Evidence for Nondissociative Ligand Exchange within [4+2]-Coordinate Phosphorus Species in Solution.
[4+2]-Coordinate phosphorus compounds, [bis(8-(dimethylamino)-1-naphthyl)]phenylphosphane, [bis(8-(dimethylamino)-1-naphthyl)]phenylphosphane sulfide, [bis(8-(dimethylamino)-1-naphthyl)]phenylphosphonium bromide, [bis(8-(dimethylamino)-1-naphthyl)]methylphosphane, and [bis(8-(dimethylamino)-1-naphthyl)]phosphane oxide, with two identical bidentate (8-(dimethylamino)-1-naphthyl) ligands have asymmetrical geometries in solution and undergo intramolecular nondissociative ligand exchange as shown by dynamic (1)H NMR studies. The DeltaG() values for this process were found to lie in the range 56.2-61.7 kJ mol(-)(1). The (1)H NMR study for bis[(8-(dimethylamino)-1-naphthyl)]phenylphosphane sulfide has revealed that two hexacoordinate isomers coexist in solution in a solvent dependent ratio. Their interconversion in solution is consistent with an intramolecular 1,2-shift of adjacent ligands.
Chauhan
Moni
M
Laboratoire de Chimie Moléculaire et Organisation du Solide, UMR 5637 CNRS, Université Montpellier II, Place E. Bataillon, F-34095 Montpellier Cedex 5, France, and Laboratoire de Chimie Organique, ESA 5076, Ecole Normale Supérieure de Chimie, 8 Rue de l'Ecole Normale, F-34296 Montpellier Cedex 5, France.
Chuit
Claude
C
Fruchier
Alain
A
Reyé
Catherine
C