Synthesis and properties of rhodium(I) chloranilate and 2,5-dihydroxy-1,4-benzoquinonate complexes. Crystal structures of the binuclear (Rh2(mu-CA)(cod)2) and tetranuclear (Rh4(mu-CA)2(cod)4) complexes (CA = chloranilate anion)

The binuclear complexes Rh2(mu-L)(diolefin)2 L = CA2-, DHBQ2-; diolefin = cycloocta-1,5-diene (cod), norborna-1,5-diene, tetrafluoro- (5,6)bicyclo(2.2.2)octa-2,5,7-triene were synthesized from the reaction of Rh2(mu-OMe)2(diolefin)2 with chloranilic acid (H2CA) or 2,5-dihydroxy-1,4-benzoquinone (H2DHBQ). The complex Rh4(mu-CA)2(cod)4 was also obtained and upon dissolution in a solvent and crystallization gave Rh2(mu-CA)(cod)2. The complexes were characterized by X-ray diffraction techniques.