title: Synthesis and characterization of optically active and racemic forms of cyclometalated Rh(III) complexes. An experimental and theoretical emission study.
abstract: The optically active cyclometalated Rh(III) complexes, delta[Rh(thpy4,5p(R,R)py)(2)TAP]Cl, lambda[Rh(thpy4,5p(S,S)py)(2)TAP]Cl, and delta[Rh(phpy4,5p(R,R)py)(2)TAP]Cl (where TAP = 1,4,5,8-tetraazaphenanthrene, thpy4,5p(R,R)py = (8R,10R)-2-(2'-thienyl)-4,5-pinenopyridine and phpy4,5p(R,R)py = (8R,10R)-2-(2'-phenyl)-4,5-pinenopyridine) have been prepared and characterized. Their photophysics has been examined in parallel with that of rac[Rh(thpy)(2)TAP]Cl and rac[Rh(phpy)(2)TAP]Cl. Their behaviors have been rationalized from results of TD-DFT calculations. The complexes with thienylpyridine (thpy) as cyclometalating ligands exhibit (3)CT (from thpy to TAP) and (3)LC(pi-pi) (centered on thpy) emissions in a solvent matrix at 77 K and one (3)CT luminescence at room temperature. In contrast, with phenylpyridine (phpy), the complexes show only one (3)CT emission (from phpy to TAP) at both temperatures.
authors.affiliation: Organic Chemistry and Photochemistry, Free University of Brussels, CP: 160/08, 50 avenue Franklin Roosevelt, 1050 Brussels, Belgium.
authors.forename: Liana
authors.initials: L
authors.lastname: Ghizdavu
authors.forename: Olivier
authors.initials: O
authors.lastname: Lentzen
authors.forename: Stephan
authors.initials: S
authors.lastname: Schumm
authors.forename: André
authors.initials: A
authors.lastname: Brodkorb
authors.forename: Cécile
authors.initials: C
authors.lastname: Moucheron
authors.forename: Andrée
authors.initials: A
authors.lastname: Kirsch-de Mesmaeker