The Friedländer condensation of (1R,5S)-(+)- and (1S,5R)-(-)-nopinone with 8-aminoquinoline-7-carbaldehyde leads to the corresponding enantiomerically pure (2,3-b)-pineno-1,10-phenanthrolines. Coordination of these ligands with Cu(I) affords non-interconvertable chiral complexes which show equal and opposite Cotton effects in their CD spectra as well as identical half-wave oxidation potentials of +0.37 V and identical MLCT absorptions at 442 nm. Both complexes are nonemissive at 298 and 77 K. Stern-Volmer quenching studies were carried out with optically pure Δ- and Λ-[Ru(bpy)3]2+ and racemic [Ru(dpb)3]2+ as donors (bpy = 2,2′-bipyridine and dpb = 4,4′-diphenyl-bpy). Neither study provides any evidence of enantioselective quenching, indicating that energy or electron transfer may be occurring through a distance where chiral recognition is unimportant.
Riesgo, E.C., Credi, A., De Cola, L., Thummel, R.P. (1998). Diastereoselective Formation and Photophysical Behavior of a Chiral Copper(I) phenanthroline Complex. INORGANIC CHEMISTRY, 37(9), 2145-2149 [10.1021/ic971267a].
Diastereoselective Formation and Photophysical Behavior of a Chiral Copper(I) phenanthroline Complex
Credi A.;De Cola L.;
1998
Abstract
The Friedländer condensation of (1R,5S)-(+)- and (1S,5R)-(-)-nopinone with 8-aminoquinoline-7-carbaldehyde leads to the corresponding enantiomerically pure (2,3-b)-pineno-1,10-phenanthrolines. Coordination of these ligands with Cu(I) affords non-interconvertable chiral complexes which show equal and opposite Cotton effects in their CD spectra as well as identical half-wave oxidation potentials of +0.37 V and identical MLCT absorptions at 442 nm. Both complexes are nonemissive at 298 and 77 K. Stern-Volmer quenching studies were carried out with optically pure Δ- and Λ-[Ru(bpy)3]2+ and racemic [Ru(dpb)3]2+ as donors (bpy = 2,2′-bipyridine and dpb = 4,4′-diphenyl-bpy). Neither study provides any evidence of enantioselective quenching, indicating that energy or electron transfer may be occurring through a distance where chiral recognition is unimportant.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
