Syntheses, structures, and reactivity of new pentamethylcyclopentadienyl-rhodium(III) and -irridium(III) 4-acyl-5-pyrazolonate complexes

Rh(III) diketonate complexes of formula [Cp*M(Q)Cl] (M=Rh or Ir, Cp*=pentamethylcyclopentadienyl, HQ=1-phenyl-3-mthyl-4R(C=O)-pyrazol-5-one) is easily synthesized by reaction of [Cp*MCl2]2 with the adequate sodium salt NaQ. [Cp*M(Q)Cl] complexes exist as enantiomers, both in the solid state and in solution, the mental being a center of chirality. The [Cp*M(Q)Cl] complexes are stable in solid state and in the atmosphere for a long time, and they are also stable in weak polar solvents and up to 55 degree Celsius.