Two fac-tricarbonylrhenium(I) azadipyrromethene (ADPM) complexes: ligand-substitution effect on crystal structure.

The crystal structures of fac-(acetonitrile-κN)(2-{[3,5-bis(4-methoxyphenyl)-2H-pyrrol-2-ylidene-κN(1)]amino}-3,5-bis(4-methoxyphenyl)-1H-pyrrol-1-ido-κN(1))tricarbonylrhenium(I)-hexane-acetonitrile (2/1/2), [Re(C36H30N3O4)(CH3CN)(CO)3]·0.5C6H14·CH3CN, (2), and fac-(2-{[3,5-bis(4-methoxyphenyl)-2H-pyrrol-2-ylidene-κN(1)]amino}-3,5-bis(4-methoxyphenyl)-1H-pyrrol-1-ido-κN(1))tricarbonyl(dimethyl sulfoxide-κO)rhenium(I), [Re(C36H30N3O4)(C2H6OS)(CO)3], (3), at 150 K are reported. Both complexes display a distorted octahedral geometry, with a fac-Re(CO)3 arrangement and one azadipyrromethene (ADPM) chelating ligand in the equatorial position. One solvent molecule completes the coordination sphere of the Re(I) centre in the remaining axial position. The ADPM ligand shows high flexibility upon coordination, while retaining its π-delocalized nature. Bond length and angle analyses indicate that the differences in the geometry around the Re(I) centre in (2) and (3), and those found in three reported fac-Re(CO)3-ADPM complexes, are dictated mainly by steric factors and crystal packing. Both structures display intramolecular C-H...N hydrogen bonding. Intermolecular interactions of the Csp(2)-H...π and Csp(2)-H...O(carbonyl) types link the discrete monomers into extended chains.