FIRST STRUCTURAL CONFIRMATION OF DIFFERENT GEOMETRICAL-ISOMERS IN THESAME CRYSTAL-LATTICE - THE CRYSTAL-STRUCTURE OF NZOYLACETONATOCARBONYLTRIPHENYLPHOSPHINERHODIUM(I)

The first structural confirmation of two different [Rh(BA)(CO)(PPh(3)) ] isomers (BA = benzoylacetonate, CH3(CO)CH(CO)C6H5), namely one with PPh(3) cis to the oxygen atom nearest to the phenyl group and the seco nd isomer with PPh(3) trans to the oxygen nearest to the phenyl group, in the same crystal lattice is reported. The small influence of the d ifferent substituents is illustrated by the near equal Rh-O, Rh-P and Rh-C bond distances in the two different isomers. The structure crysta llizes in the triclinic system, space group P $($) over bar$$ 1 with a = 15.625(2), b = 19.138(2), c = 8.891(2) Angstrom, alpha = 95.66(1), beta = 74.43(1), gamma = 90.52(1)degrees and Z = 4. The Rh-P, Rh-CO an d Rh-O bond distances for isomer I are 2.249(3), 1.739(14), 2.032(8) a nd 2.079(8) Angstrom, respectively, while the corresponding bond dista nces for isomer II are 2.248(3), 1.768(14), 2.018(8) and 2.057(7) Angs trom, respectively.