TY - JOUR A1 - Schwarze, Thomas A1 - Dosche, Carsten A1 - Flehr, Roman A1 - Klamroth, Tillmann A1 - Löhmannsröben, Hans-Gerd A1 - Saalfrank, Peter A1 - Cleve, Ernst A1 - Buschmann, Hans-Jürgen A1 - Holdt, Hans-Jürgen T1 - Combination of a CT modulated PET and an intramolecular excimer formation to quantify PdCl2 by large fluorescence enhancement N2 - The [6.6](9,10)anthracenophane 1 (Scheme 1) is a selective fluoroionophore for the detection of PdCl2 with a large fluorescence enhancement factor (I/I-0 > 250). Y1 - 2010 UR - http://pubs.rsc.org/en/content/articlehtml/2010/cc/b919973j U6 - https://doi.org/10.1039/B919973j SN - 1359-7345 ER - TY - JOUR A1 - Schwarze, Thomas A1 - Dosche, Carsten A1 - Flehr, Roman A1 - Klamroth, Tillmann A1 - Löhmannsröben, Hans-Gerd A1 - Saalfrank, Peter A1 - Cleve, Ernst A1 - Buschmann, Hans-Jürgen A1 - Holdt, Hans-Jürgen T1 - Combination of a CT modulated PET and an intramolecular excimer formation to quantify PdCl2 by large fluorescence enhancement Y1 - 2010 UR - http://www.rsc.org/ej/CC/2010/b919973j.pdf SN - 1359-7345 ER - TY - JOUR A1 - Schwarze, Thomas A1 - Mickler, Wulfhard A1 - Dosche, Carsten A1 - Flehr, Roman A1 - Klamroth, Tillmann A1 - Löhmannsröben, Hans-Gerd A1 - Saalfrank, Peter A1 - Holdt, Hans-Jürgen T1 - Systematic investigation of photoinduced electron transfer controlled by internal charge transfer and its consequences for selective PdCl2 coordination N2 - Fluoroionophores of fluorophore-spacer-receptor format were prepared for detection of PdCl2 by fluorescence enhancement. The fluorophore probes 1-13 consist of a fluorophore group, in alkyl spacer and a dithiomaleonitrile PdCl2 receptor. First, varying the length of the alkylene spacer (compounds 1-3) revealed, dominant through-space pathway for oxidative photoinduced electron transfer (PET) in CH2-bridged dithiomaleonitrile fluoroionophores. Second. fluorescent probes 4-9 containing two anthracene or pyrene fragments connected through CH2 bridges to the dithiomaleonitrile unit were synthesized. Modulation of the oxidation potential (E-Ox) through electron-withdrawing or -donating groups on the anthracene moiety regulates file thermodynamic driving force for oxidative PET (Delta G(PET)) in bis(anthrylmethylthio)maleonitriles and therefore the fluorescence quantum yields (Phi(f)), too. The new concept was confirmed and transferred to pyrenyl ligands, and fluorescence enhancements (FE) greater than 3.2 in the presence of PdCl2 were achieved by 7 and 8 (FE=5.4 and 5.2). Finally, for comparison, monofluorophore ligands 10-13 were synthesized. Y1 - 2010 UR - http://onlinelibrary.wiley.com/doi/10.1002/chem.200902281/pdf U6 - https://doi.org/10.1002/chem.200902281 SN - 0947-6539 ER - TY - JOUR A1 - Schwarze, Thomas A1 - Mickler, Wulfhard A1 - Dosche, Carsten A1 - Flehr, Roman A1 - Klamroth, Tillmann A1 - Löhmannsröben, Hans-Gerd A1 - Saalfrank, Peter A1 - Holdt, Hans-Jürgen T1 - Systematic investigation of photoinduced electron transfer controlled by internal charge transfer and its consequences for selective PdCl2 coordination N2 - Fluoroionophores of fluorophore-spacer-receptor format were prepared for detection of PdCl2 by fluorescence enhancement. The fluorescent probes 1-13 consist of a fluorophore group, an alkyl spacer and a dithiomaleonitrile PdCl2 receptor. First, varying the length of the alkylene spacer (compounds 1-3) revealed a dominant through-space pathway for oxidative photoinduced electron transfer (PET) in CH2-bridged dithiomaleonitrile fluoroionophores. Second, fluorescent probes 4-9 containing two anthracene or pyrene fragments connected through CH2 bridges to the dithiomaleonitrile unit were synthesized. Modulation of the oxidation potential (EOx) through electron-withdrawing or -donating groups on the anthracene moiety regulates the thermodynamic driving force for oxidative PET (GPET) in bis(anthrylmethylthio)maleonitriles and therefore the fluorescence quantum yields (f), too. The new concept was confirmed and transferred to pyrenyl ligands, and fluorescence enhancements (FE) greater than 3.2 in the presence of PdCl2 were achieved by 7 and 8 (FE=5.4 and 5.2). Finally, for comparison, monofluorophore ligands 10-13 were synthesized. Y1 - 2010 UR - http://www3.interscience.wiley.com/journal/26293/home SN - 0947-6539 ER - TY - JOUR A1 - Schweizer, S. A1 - Schuster, T. A1 - Junginger, Matthias A1 - Siekmeyer, Gerd A1 - Taubert, Andreas T1 - Surface modification of ickel/Titanium Alloy and Titanium Surfaces via a Polyelectrolyte Multilayer/Calcium Phosphate Hybrid Coating N2 - The report shows that simple LbL deposition of positively charged chitosan and negatively charged heparin can be used to efficiently modify the native surface of both NiTi and Ti without any previous treatments. Moreover, mineralization of the polymer multilayers with calcium phosphate leads to surfaces with low contact angles around 70 and 20 degrees for NiTi and Ti, respectively. This suggests that a polymer multilayer/calcium phosphate hybrid coating could be useful for making NiTi or Ti implants that are at the same time antibacterial (via the chitosan), suppress blood clot formation (via the heparin), and favor fast endothelialization (via the improved surface hydrophilicity compared to the respective neat material). Y1 - 2010 UR - http://onlinelibrary.wiley.com/doi/10.1002/mame.200900347/pdf U6 - https://doi.org/10.1002/mame.200900347 SN - 1438-7492 ER - TY - JOUR A1 - Senge, Mathias O. A1 - Shaker, Yasser M. A1 - Pintea, Monica A1 - Ryppa, Claudia A1 - Hatscher, Sabine S. A1 - Ryan, Aoife A1 - Sergeeva, Yulia T1 - Synthesis of meso-substituted ABCD-Type porphyrins by functionalization reactions N2 - Considerable progress has been made in recent years in the search for synthetic methods leading to functionalized porphyrins, especially for modification of either the beta- or meso positions. For the latter, total synthesis based on condensation methods or partial synthesis through functionalization of preformed porphyrin have emerged as possible methods. The increasing number of possible technical and medicinal applications for unsymmetrically meso-substituted porphyrins requires straightforward methods for the preparation of the so-called ABCD-porphyrins, i.e., porphyrins with up to four different meso substituents. Here, we describe new strategies for the synthesis of ABCD-type porphyrins based on porphyrin reactions with organolithium reagents and the use of Pd-catalyzed coupling reactions. With the whole repertoire of contemporary functionalization methods, a comprehensive analysis and comparison of the various strategies for A-, AB-, A(2)B-, ABC-, A(2)BC- and ABCD-type porphyrins is given. In addition, we report on the synthesis of new functionalized derivatives for some of these porphyrin classes. In practical terms and taking an applied-science- oriented approach, the synthesis of unsymmetrically meso-substituted porphyrins is best accomplished by a combination of well-developed condensation methods with subsequent functionalization. by organolithium compounds or transition-metal- catalyzed coupling protocols. The methods described are suitable for the preparation of porphyrins for many divergent applications ranging over amphiphilic porphyrins for photodynamic therapy, push-pull systems for optical applications and chiral systems useful in catalysis to donor-acceptor systems suitable for electron-transfer studies. Y1 - 2010 UR - http://www3.interscience.wiley.com/cgi-bin/jhome/27380/ U6 - https://doi.org/10.1002/ejoc.200901113 SN - 1434-193X ER - TY - JOUR A1 - Shainyan, Bagrat A. A1 - Moskalik, Mikail Yu A1 - Starke, Ines A1 - Schilde, Uwe T1 - Formation of unexpected products in the attempted aziridination of styrene with trifluoromethanesulfonyl nitrene N2 - The reaction of styrene with trifluoromethanesulfonyl nitrene generated from trifluoromethanesulfonamide in the system (t-BuOCl+NaI) results in the formation of trifluoro-N-[2-phenyl-2-(trifluoromethylsulfonyl) aminoethyl]methanesulfonamide, 1-pheny1-2-iodo-ethanol, and 2,5-diphenyl-1,4-bis(trifluoromethyl sulfonyl)piperazine rather than the expected product of aziridination, 2-phenyl-1-(trifluoromethylsulfonyl) aziridine. The mechanism of the reaction is discussed. Y1 - 2010 UR - http://www.sciencedirect.com/science/journal/00404020 U6 - https://doi.org/10.1016/j.tet.2010.08.070 SN - 0040-4020 ER - TY - JOUR A1 - Siegmann, Rebekka A1 - Beuermann, Sabine T1 - Individual rate coefficients for 1H,1H,2H,2H-tridecafluorooctyl methacrylate radical polymerizations N2 - Kinetic data for radical polymerizations of 1H,1H,2H,2H-tridecafluorooctyl methacrylate (TDFOMA) in bulk is reported. Pulsed laser initiated polymerizations yield propagation rate coefficients, k(p), which are by a factor of 1.9 higher than methyl methacrylate k(p). The activation energy of TDFOMA k(p) is not significantly different from that of alkyl methacrylates. Chain-length averaged termination rate coefficients were estimated from chemically initiated polymerizations with in-line FT-NIR spectroscopic monitoring of monomer conversion. Up to 30% of monomer conversion TDFOMA termination rate coefficients are only slightly below MMA low conversion values. The result is suggested to be due to less interactions between the macroradicals compared to nonfluorinated systems. Y1 - 2010 UR - http://pubs.acs.org/journal/mamobx U6 - https://doi.org/10.1021/Ma902653b SN - 0024-9297 ER - TY - JOUR A1 - Siegmann, Rebekka A1 - Jelicic, Aleksandra T1 - Propagation and termination kinetics of PEGylated methacrylate radical polymerizations N2 - Propagation and chain-length averaged termination rate coefficients, k(p) and , for radical polymerizations of methacrylates carrying poly(ethylene glycol) (PEG) units are reported. kp derived from pulsed laser initiated polymerizations in bulk, in organic solvents, and in ionic liquids follows the methacrylate-type family behavior. Contrary, diffusion controlled k(t) values obtained from chemically initiated polymerizations with in-line FT- NIR monitoring of monomer conversion are strongly affected by the PEG units in the ester group. Compared to alkyl methacrylates is unexpectedly high. Moreover, of poly(ethylene glycol) ethyl ether methacrylate shows a significant reduction in k(t) already at 15% conversion, whereas dodecyl methacrylate is constant up to at least 70% conversion. Y1 - 2010 UR - http://www3.interscience.wiley.com/journal/10003495/home U6 - https://doi.org/10.1002/macp.200900527 SN - 1022-1352 ER - TY - JOUR A1 - Skrabania, Katja A1 - von Berlepsch, Hans A1 - Böttcher, Christoph A1 - Laschewsky, André T1 - Synthesis of ternary, hydrophilic-lipophilic-fluorophilic block copolymers by consecutive RAFT polymerizations and their self-assembly into multicompartment micelles N2 - Linear amphiphilic diblock and ternary triblock copolymers were synthesized by the RAFT method in three Successive Steps, using oligo(ethylene oxide) monomethyl ether acrylate, butyl or 2-ethylhexyl acrylate, and 1H, 1H, 2H, 2H-perfluorodecyl acrylate. The diblock and the triblock copolymers, which consist of a hydrophilic, a lipophilic, and a fluorophilic block, self-assemble in water into spherical micellar aggregates. Imaging by cryogenic transmission electron microscopy (cryo-TEM) revealed that the cores of the micellar aggregates made from these "triphilic" copolymers undergo local phase separation to form various ultrastructures, which depend sensitivity on the given block sequence. While the sequence hydrophilic-lipophilic-fluorophilic resulted in multicompartment cores with core-shell-corona morphology, the sequence lipophilic-hydrophilic-fluorophilic provided new "patched double micelle" and larger "soccer ball" structures. Y1 - 2010 UR - http://pubs.acs.org/journal/mamobx U6 - https://doi.org/10.1021/Ma901913f SN - 0024-9297 ER -