The crystal and molecular structure of trans-chlorocarbonylbis(triphenylphosphine)rhodium(I) in its monoclinic form

The structure of the title compound, RhCl(CO)(PPh3)2, has been investigated in its monoclinic modification. It belongs to space group P21/n (No. 14), with cell constants a 12.182(3), b 24.285(5), c 11.894(3) Å, β 113.10(2)°, Z = 4. The structure was solved by conventional Patterson and Fourier methods, on the basis of 4295 significant counter data, by least-squares methods to a final conventional R values of 0.051. The complex exhibits a square planar coordination, with the two bulky phosphine ligands in mutually trans positions. The mean value of the RhP bond lengths is 2.326 Å. The RhCl, RhC and CO bond lengths are 2.371(2), 1.810(7), and 1.144(8) Å, respectively. The structure is compared with those of similar species and the small differences observed between the monoclinic and triclinic modifications of this compound are discussed. © 1973.