Andreas Strasser

Optical properties of tris(cyclopentadienyl)gadolinium. Luminescence from an interligand triplet under ambient conditions

Abstract The organometallic compound GdCp 3 (Cp=cyclopentadienyl) in ether solution shows a green luminescence ( λ max =523 nm, φ =0.2). It is suggested that this emission originates from a triplet of the Cp 3 3− moiety.

Coexisting intraligand fluorescence and phosphorescence of hafnium(IV) and thorium(IV) porphyrin complexes in solution

Abstract The closed-shell metalloporphyrins Hf(TPP)(OAc)2 and Th(TPP)(acac)2 (TPP=dianion of tetraphenylporphyrin, OAc=acetate, acac=acetylacetonate) display intraligand fluorescence and additional heavy-atom-induced intraligand phosphorescence, which is observed at room temperature in fluid solution and very efficiently quenched by O2 with potential significance for the sensing of trace amounts of dioxygen.

Synthesis and spectroscopic properties of anhydrotetracyclineplatinum(II)dichloride

Abstract The reaction of tetracycline with K2PtCl4 in glacial acetic acid leads to the dehydration of tetracycline to anhydrotetracycline (ahtc) which coordinates as a bidentate ligand to the PtCl2 moiety. The composition of Pt(ahtc)Cl2 is confirmed by elemental analysis and mass spectrometry. On the basis of the electronic spectra it is suggested that the coordination takes place at the A ring of ahtc while the BCD ring system is preserved as separate chromophore. It is characterized by a long-wavelength absorption and fluorescence which appear at λmax=428 and 550 nm, respectively, for the free ahtc ligand and λmax=425 and 550 nm for Pt(ahtc)Cl2.

Synthesis and spectroscopic properties of (oxytetracycline)tricarbonylrhenium(I) chloride

Abstract The complex (OTC)Re I (CO) 3 Cl, with OTC=oxytetracycline, has been prepared and characterized by elemental analysis, ESI–MS, IR and UV–Vis spectroscopy. The complex, which contains OTC as a bidentate ligand, shows an OTC intraligand fluorescence at λ max =570 nm with Φ =2×10 −3 at λ exc =390 nm.

Synthesis, Electronic Spectra and Solvent-Induced Reversible Dissociation of Diphosphine(hexafluoroacetylacetonato)copper(I) Complexes

The complexes CuI(P-P)(hfac) with P-P = 1,2-bis(diphenylphosphino)ethane (diphos), 1,3-bis-(diphenylphosphino)propane (prophos), 2,2’-bis(diphenylphosphino)-1,1’-binaphthyl (binap) and hfac = hexafluoroacetylacetonate were synthesized and spectroscopically characterized. In the solid state or in solutions of non-polar solvents these compounds are yellow owing to a long-wavelength (hfac− →P-P) ligand-to-ligand charge transfer absorption. In coordinating solvents such as CH3CN the complexes undergo a reversible dissociation according to the equation: Cu(P-P)(hfac) + n CH3CN ⇌ [Cu(P-P)(CH3CN)n]+hfac−. While the complexes are not luminescent the ion pairs [Cu(P-P)(CH3CN)n]+hfac− are emissive at 77 K. The cations and the anions show separate emissions as indicated by the excitation spectra.