Reaction of [RhH(NH2C6H4PPh2-o)2Cl]Cl with air; characterisation of the products by X-ray structure analysis of cis-[Rh(NH2C6H4PPh2-o)(NHC6H4PPh2-o)Cl2] and trans-[Rh(NH2C6H4PPh2-o)2Cl2][p-MeC6H4SO3]·MeCN

Abstract

The chlorohydridorhodium(III) complex of (o-diphenylphosphinophenyl)amine, [RhH(NH₂C₆H₄PPh₂-o)₂Cl]Cl (1a), formed by oxidative addition of HCl to [Rh(NH₂C₆H₄PPh₂-o)₂]BF₄(2b), was found to react with air to give two products. These have been characterised by X-ray structure analysis as the cis-dichloro-complex [Rh(NH₂C₆H₄PPh₂-o)(NHC₆H₄PPh₂-o)Cl₂](6), containing an amino- and amido-donor group, and the trans-dichloro-complex [Rh(NH₂C₆H₄PPh₂-o)₂Cl₂][p-MeC₆H₄SO₃](8). Crystals of (6) are monoclinic, space group P2₁/n, with a= 17.153(3), b= 18.667(3), c= 9.891(2)Å, β= 91.77(3)°, and Z= 4. Blocked full-matrix refinement using 3 501 unique data [I 3σ(I), 3 ⩽θ⩽ 25°] gave R= 0.0487, R′= 0.0511. Complex (8) crystallises, with a molecule of acetonitrile as solvate, in the monoclinic space group I2/c with a= 18.394(4), b= 14.380(3), c= 16.378(3)Å, β= 96.67(4)°, and Z= 4. Blocked full-matrix refinement of 2 741 reflections with I 3σ(I)(3 ⩽θ⩽ 25°) gave R= 0.0638 and R′= 0.0698. The cation of (8) has exact C₂ symmetry. A mechanism for the reaction is proposed which involves peroxo- and hydrogenperoxo-species.