Transition Metal Complexes with Bidentate Ligands Spanning trans-Positions. Part XIII. Preparation,properties and crystal and molecular structures of chlorocarbonyl-2,11-bis(diphenylphosphinophenyl) benzo[c]phenanthreneiridium (I) and trichlorocarbonyl-2,11-bis(diphenylphosphinomethyl) benzo[c]phenanthreneiridium(III)

The complex [IrCl₃(CO)( 1 )]( 4,1 =2,11-bis (diphenylphosphinomethyl)benzo[c]phenanthrene) has been prepared by CuCl₂-oxidation of [IrCl(CO)( 1 )]( 2a ). It is shown that the chlorine oxidation of 2a gives a mixture of products whose composition depends on the reaction conditions. The X-ray crystal structures of 2a and 4 have been determined. The small conformational differences observed for the trans-spanning ligand 1 in the two complexes are likely to be caused by the difference in Ir-P bond lengths in square planar 2a and octahedral 4 (2.310(4) and 2.411(3) Å, respectively).