Pentacarbonyl(4-phenylpyridine)-tungsten(0) and pentacarbonyl-(2-phenylpyridine)chromium(0)

In pentacarbonyl(4-phenylpyridine)tungsten(0), [W(C11H9N)-(CO)(5)], the molecules have mm site symmetry and the pyridine ligand, with m symmetry, is completely planar. In pentacarbonyl(2-phenylpyridine)chromium(0), [Cr(C11H9N)-(CO)(5)], the molecules are in general positions and the phenyl and pyridine rings of the ligand are twisted by 67.7 (3)degrees with respect to one another by rotation about the CDC bond joining them. In both compounds, the axial M-C-carbonyl bond trans to the M-N-ligand bond is significantly shorter than the equatorial M-C-carbonyl bonds.