Crystal structures of (η-cyclo-octa-1,5-diene)bis(1,3-di-methyl-imidazol-2-yl-idene)iridium(I) iodide and (η-cyclo-octa-1,5-diene)bis-(1,3-di-ethyl-imidazol-2-yl-idene)iridium(I) iodide.

The title complexes, (η-cyclo-octa-1,5-diene)bis-(1,3-di-methyl-imidazol-2-yl-idene)iridium(I) iodide, [Ir(CHN)(CH)]I, () and (η-cyclo-octa-1,5-di-ene)bis-(1,3-di-ethyl-imidazol-2-yl-idene)iridium(I) iodide, [Ir(CHN)(CH)]I, (), were prepared using a modified literature method. After carrying out the oxidative addition of the amino acid l-proline to [Ir(COD)(IMe)]I in water and slowly cooling the reaction to room temperature, a suitable crystal of was obtained and analyzed by single-crystal X-ray diffraction at 100 K. Although this crystal structure has previously been reported in the space group, it was highly disordered and precise atomic coordinates were not calculated. A single crystal of was also obtained by heating the complex in water and letting it slowly cool to room temperature. Complex was found to crystallize in the monoclinic space group 2/, while crystallizes in the ortho-rhom-bic space group , both with = 4.