Three-coordinate, phosphine-ligated azadipyrromethene complexes of univalent group 11 metals.
Tetraarylazadipyrromethenes are Lewis basic, red-light absorbing dyes with optical properties conducive to sensing and therapeutic applications. Recently, transition metal complexes of these ligands have been described. Here, we report a series of three-coordinate Group 11 complexes of unsubstituted and methoxy-substituted tetraarylazadipyrromethenes. In each, two pyrrole nitrogens chelate a d(10) metal ion; triphenyl- or triethylphosphine occupies a third coordination site. New complexes are characterized by multinuclear NMR, X-ray crystallography, optical absorption and emission spectroscopy, and elemental analysis. Solid-state structures show trigonal planar geometries about the metal centers, and reveal pervasive intra- and intermolecular pi-stacking interactions. Visible light absorption intensifies with metal binding, in some cases shifting to longer wavelengths. The complexes weakly luminesce in the red region; emission wavelengths and quantum yields are similar to those of free azadipyrromethenes. Methoxy-substitution on the ligand red-shifts optical features, whereas substitution of triethylphosphine for triphenylphosphine in the third coordination site has minimal structural or spectral consequences.
Teets
Thomas S
TS
Department of Chemistry, Case Western Reserve University, Cleveland, Ohio 44106, USA.
Updegraff
James B
JB
Esswein
Arthur J
AJ
Gray
Thomas G
TG
D001372:Aza Compounds / Q000737:chemistry*; D003198:Computer Simulation; D018360:Crystallography, X-Ray; D008024:Ligands; D008956:Models, Chemical; D008958:Models, Molecular; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D010720:Phosphines / Q000737:chemistry*; D011162:Porphobilinogen / Q000031:analogs & derivatives* / Q000737:chemistry; D013237:Stereoisomerism; D028561:Transition Elements / Q000737:chemistry*
D001372:Aza Compounds; D008024:Ligands; D009942:Organometallic Compounds; D010720:Phosphines; D028561:Transition Elements; C507544:dipyrromethene; D011162:Porphobilinogen