OLEFIN LIGANDS. SYNTHESES AND STRUCTURES OF 2,6-DIALLYLPYRIDINE (DAP) COMPLEXES OF RHODIUM(I); CRYSTAL STRUCTURES OF AND

Article abstract of DOI:10.1016/0022-328X(86)80302-3

The olefinic ligand 2,6-diallylpyridine (DAP) has been shown to react with various rhodium(I) compounds to give complexes of the type _n, RhCl(L)(DAP) (L = CO, PPh3), Y (diene = cycloocta-1,5-diene (COD), bicyclo<2.2.1>hepta-2,5-diene (NBD); Y = , , ClO4).These complexes have been characterised by chemical and spectroscopic means.In addition, the crystal structures of (1) and (2) have been determined by X-ray methods.Crystals of 1 are triclinic, space group P<*>, with Z = 2 in a unit cell of dimensions a 10.481(4), b 13.041(4), c 10.456(4) Angstroem, α 106.77(2), β 112.10(2), γ 79.57(1) deg.Crystals of 2 are monoclinic, space group P2₁/c, with Z = 4 in a unit cell of dimension a 14.303(8), b 10.453(5), c 13.412(6) Angstroem, β 110.95(4) deg.Both structures were solved from diffractometer data by direct and Fourier methods and refined by blocked full-matrix least-squares to R = 0.0316 (2204 observed reflections) for 1 and by full matrix least-squares to R = 0.0545 (1897 observed reflections) for 2.The crystals consist of cationic ⁺ and anionic ^- (1) and ^- (2) complexes.The cations are similar in the two compounds, and the coordination around the Rh¹ atoms can be described as trigonal bipyramidal, with a short Rh-N axial bond and four η²-C=C olefinic interactions.The DAP acts as a tridentate ligand.