SYNTHESIS AND CHARACTERIZATION OF PHOSPHINIMINE-SUBSTITUTED TRIFLUORO-P-BENZOQUINONES OR TRICHLORO-P-BENZOQUINONES AND THEIR CATIONIC RH(I)COMPLEXES - THE CRYSTAL AND MOLECULAR-STRUCTURE OF RICHLORO-2-(TRIPHENYLPHOSPHINIMINO)-P-BENZOQUINONE

Reaction of tetrafluoro- or tetrachloro-p-benzoquinone with silylated phosphoranimines R(2)R'P-NSiMe(3) (R=Ph, Me) yields very highly colore d monosubstituted derivatives of the p-quinone that acr as two-electro n accepters showing clean, reversible CV traces. The molar absorptivit y values are typical of dyes. These Ligands also form chelate complexe s with Rh(I) precursors using the quinone oxygen and the imine nitroge n donor sites. One of the quinone derivatives, richloro-2(triphenylpho sphinimino)-p-benzoquinone, has been structurally characterized. The i minated quinone shows a normal P-N bond length (1.597(2) Angstrom) and P-N-C angle (P-N-C(3) 132.7(2)degrees). The N-C(3) bond, 1.327(3) Ang strom, is a little shorter as is expected for the establishment of a c onjugated structure between the phosphinimine substituent and the quin one ring. Some steric crowding pushes the Cl and N substituents on the quinone ring out of the plane of the ring.