TY - JOUR A1 - Kleinpeter, Erich A1 - Grotjahn, Manuela A1 - Klinka, Karel D. A1 - Drexler, Hans-Joachim A1 - Holdt, Hans-Jürgen T1 - Conformational and complexational study of some maleonitrile mixed oxadithia crown ethers by NMR spectroscopy and molecular modelling N2 - The macrocyclic ring interconversion of four maleonitrile mixed oxadithia crown ethers of variable ring size, mn-12-S2O2, mn-15-S2O3, mn-18-S2O4 and fn-12-S2O2, were studied by 1H and 13C NMR spectroscopy and by molecular modelling. The barriers to ring interconversion were estimated using variable temperature NMR spectroscopy and from the calculated activation energies, together with the spin-lattice relaxation times of the CH2 carbon atoms, conclusions were drawn regarding the intramolecular flexibility of the crown ethers in both the free state as well as the complexed state incorporating either AgI, BiIII, SbIII, PdII or PtII metal cations. Furthermore, both the stoichiometry of the complexes and the coordination sites of the crown ethers to the various cations were also clearly implicated. Molecular modelling was also utilised to ascertain the preferred conformers of the four compounds and their corresponding complexes, the results of which corroborated the experimental NMR results to a high degree. Y1 - 2001 ER - TY - JOUR A1 - Holdt, Hans-Jürgen A1 - Drexler, Hans-Joachim A1 - Starke, Ines A1 - Grotjahn, Manuela A1 - Kleinpeter, Erich T1 - Homologous series of the PdCl2 and PtCl2 complexes of maleonitrile-dithiacrown ethers : synthesis, crystal structures, NMR spectroscopy and mass spectrometry Y1 - 2001 ER - TY - JOUR A1 - Drexler, Hans-Joachim A1 - Grotjahn, Manuela A1 - Kleinpeter, Erich A1 - Holdt, Hans-Jürgen T1 - A novel polymeric disilver(I) complex containing both macrocyclic- and linear-coordinate silver(I) centres : [Ag-2(mn-15S(2)O(3))](infinity)(ClO4)(2 infinity) (mn-15S(2)O(3) = maleonitrile-dithia[15]crown-5) Y1 - 1999 ER - TY - JOUR A1 - Drexler, Hans-Joachim A1 - Starke, Ines A1 - Grojahn, Manuela A1 - Reinke, H. A1 - Kleinpeter, Erich A1 - Holdt, Hans-Jürgen T1 - SbCl3, BiCl3 and Na+ Complexes of maleonitrile-dithiacrown ethers: synthesis, crystal structures and DEP-MS experiments Y1 - 1999 ER - TY - JOUR A1 - Grotjahn, Manuela A1 - Jäger, Norbert A1 - Drexler, Hans-Joachim A1 - Holdt, Hans-Jürgen A1 - Kleinpeter, Erich T1 - Molecular modeling study of the PtCl2 complexes of unsaturated S2On+1- coronands: dynamic simulations and investigation of the ring interconversion Y1 - 1999 ER - TY - JOUR A1 - Reiche, K. B. A1 - Starke, Ines A1 - Kleinpeter, Erich A1 - Holdt, Hans-Jürgen A1 - Pihlaja, Kalevi A1 - Oksaman, P. A1 - Ovcharenko, V. V. T1 - Fragmentation of imine-type meta-bridged bis(benzo crown ether)s under electron impact Y1 - 1999 ER - TY - JOUR A1 - Reiche, K. B. A1 - Starke, Ines A1 - Kleinpeter, Erich A1 - Holdt, Hans-Jürgen T1 - Host-guest complexation of imine-type meta-bridged bis(benzo crown ether)s with alkali cations in the gas phase under FAB conditions Y1 - 1998 ER - TY - JOUR A1 - Kleinpeter, Erich A1 - Starke, Ines A1 - Ströhl, D. A1 - Holdt, Hans-Jürgen T1 - NMR spectroscopic study of the solution structure and complexational behaviour of bis-benzocrown ethers Y1 - 1997 ER - TY - JOUR A1 - Grotjahn, Manuela A1 - Drexler, Hans-Joachim A1 - Jäger, Norbert A1 - Kleinpeter, Erich A1 - Holdt, Hans-Jürgen T1 - Molecular dynamic and conformational study of an unsaturated 12-crown-S202 ether and its AgI complexes Y1 - 1997 ER - TY - JOUR A1 - Kleinpeter, Erich A1 - Starke, Ines A1 - Ströhl, D. A1 - Holdt, Hans-Jürgen T1 - NMR spectroscopic study of the solution structure and complexational behaviour of bis-benzocrown ethers Y1 - 1996 ER - TY - JOUR A1 - Starke, Ines A1 - Koch, Andreas A1 - Holdt, Hans-Jürgen A1 - Kleinpeter, Erich T1 - 1H, 13C, and 15N NMR study of the solution structure of metabridged bis(benzo-15-crown-5-ether)s Y1 - 1995 ER - TY - JOUR A1 - Starke, Ines A1 - Kammer, Stefan A1 - Grunwald, Nicolas A1 - Schilde, Uwe A1 - Holdt, Hans-Jürgen A1 - Kleinpeter, Erich T1 - Complexation of diazaperylene and bisisoquinoline with transition metal ions in the gas phase studied by electrospray ionization mass spectrometry N2 - The complex formation of the ligands 1,12-diazaperylene (dap), 1,1-bisisoquinoline (bis), 2,2-bipyridine (bpy) and 1,10-phenanthroline (phen) with transition metal ions (M = Fe, Co, Ni, Cu, Zn, Ru, Os, Re, Pd, Pt, Ag and Cd) in the gas phase has been studied by electrospray ionization mass spectrometry. With the exception of Ru, Os, Fe, Ni and Cu, singly charged complexes [MLn]+ (n = 1,2) were observed. The complexes of dap and bis with Ru, Os, Fe and Ni ions, and the mixed ligand complexes with bpy and phen, are preferably of the doubly charged type [ML3]2+. In addition, collision- induced dissociation (CID) measurements were employed to evaluate the relative stabilities of these complexes. The CID experiments of mixed-ligand complexes which contain both dap and phen or dap and bpy exhibit preferential elimination of bpy, indicating that bpy is a weaker ligand than phen and dap. Y1 - 2008 ER - TY - JOUR A1 - Holdt, Hans-Jürgen A1 - Müller, Holger A1 - Potter, Matthias A1 - Kelling, Alexandra A1 - Schilde, Uwe A1 - Starke, Ines A1 - Heydenreich, Matthias A1 - Kleinpeter, Erich T1 - The first sandwich complex with an octa(thioether) coordination sphere : Bis(maleonitrile-tetrathia-12-crown- 4)silver(I) N2 - The new tetrathiacrown ethers maleonitrile-tetrathia-12-crown-4 (mn12S(4)) and maleonitrile-tetrathia-13-crown- 4 (mn13S(4)) have been prepared and characterised by X-ray crystallographic analysis. These crown ethers form 2:1, 3:2 and 1: 1 complexes with AgY (Y = BF4, PF6). The crystal structures of [Ag(mn12S(4))(2)]BF4 (3a), [Ag(mn13S(4))(2)]BF4 (4a) and [Ag-2(mn13S(4))(3)](PF6)(2) (6b) have been determined. Compound 3a contains the centrosymmetric sandwich complex cation [Ag(mn12S(4))(2)](+) where each mn12S(4) ligand is coordinated to the Ag centre in an endo manner through all four S atoms. The 2:1 complex [Ag(mn12S(4))(2)](+) is the first sandwich complex with a tetrathiacrown ether and the first complex with an octa(thioether) coordination sphere. The crystal structure of compound 4a also reveals a 2:1 complex. This complex, [Ag(mnl3S(4))(2)](+), exhibits a half-sandwich structure. One mn13S(4) ligand coordinates to Ag+ by all four S donor atoms and the other 13S(4) crown by only one S atom. Compound 6b contains a dinuclear Ag complex. The Ag complexes 3a,b-8a,b were also studied by electrospray ionisation mass spectrometry. Collision-induced dissociation (CID) was used to compare the relative stability of 2:1 complexes [AgL2]+ and 1:1 complexes [AgL](+) (L = mn12S(4), mn13S(4)). The C-13 NMR chemical shifts of 2:1 and 1:1 Ag complexes and their corresponding free ligands were also estimated and compared. The free energy of the barrier of ring inversion (Delta G(double dagger)) for [Ag(mn12S(4))(2)](+) was determined to be 64 kJmol(-1). Y1 - 2006 UR - http://www3.interscience.wiley.com/cgi-bin/jhome/27721/ U6 - https://doi.org/10.1002/ejic.200501109 SN - 1434-1948 ER - TY - JOUR A1 - Starke, Ines A1 - Fürstenberg, Sylvia A1 - Müller, Holger A1 - Holdt, Hans-Jürgen A1 - Kleinpeter, Erich T1 - Electrospray mass spectrometric studies of the complexational behavior of maleonitrile thiacrown ethers with various metals N2 - Electrospray ionization was employed to study the mass spectrometric behavior of the maleonitrile tetrathiacrown ethers mn12S(4) (1) and mn13S(4) (2) and maleonitrile pentathiacrown ether mn15S(5) (3) and of their complexes with various metal salts (MX2, M=Pd, Pt, Ni, Co, Fe; X=Cl, CrCl3, Ni(BF4)(2), TIPF6 or Cd(NO3)(2)) and Cu(SO3CF3)(2). Both singly charged, [MXL](+) and [MXL2]+, and doubly charged complexes, [MLn](2+) (n = 2-5), were observed. The formation of the different complexes consisting of the transition metal ion, the counterion and the various crown ethers and their subsequent dissociation was also studied by collision-induced dissociation measurements which were also used to evaluate the relative stabilities of the complexes. It was found that the collisional voltages for the dissociation of the complexes were generally greater in the [MXL](+) complexes than in the corresponding [MXL2]+ complexes. Copyright (c) 2006 John Wiley & Sons, Ltd Y1 - 2006 UR - http://onlinelibrary.wiley.com/doi/10.1002/rcm.2384/full U6 - https://doi.org/10.1002/Rcm.2384 ER - TY - JOUR A1 - Starke, Ines A1 - Kammer, Stefan A1 - Holdt, Hans-Jürgen A1 - Kleinpeter, Erich T1 - Stability of disubstituted copper complexes in the gas phase analyzed by electrospray ionization mass spectrometry N2 - A series of nitrogen ligand (L)/copper complexes of the type [(CuL)-L-I](+), [(CuL)-L-II(X)](+) and [(CuL2)-L- I](+) (X = Cl-, BF4-, acac(-), CH3COO- and SO3CF3-) was studied in the gas phase by electrospray ionization mass spectrometry. The following ligands (L) were employed: 1,12-diazaperylene (dap), 1,1'-bisiso-quinoline (bis), 2,2'-bipyridine (bpy), 1,10-phenanthroline (phen), 2,11-disubstituted 1,12-diazaperylenes (dap), 3,3'- disubstituted 1,1'-bisisoquinoline (bis), 5,8-dimethoxy-substituted diazaperylene (meodap), 6,6'-dimethoxy- substituted bisisoquinoline (meobis) and 2,9-dimethyl-1,10-phenanthroline (dmphen). Collision-induced decomposition measurements were applied to evaluate the relative stabilities of the different copper complexes. The influence of the spatial arrangement of the ligands, of the type of substituents and of the counter ion of the copper salts employed for the complexation was examined. Correlations were found between the binding constants of the [ML2](+) complexes in solution and the relative stabilities of the analogous complexes in the gas phase. Furthermore, complexation with the ligands 2,11-dialkylated 1,12-diazaperylenes [alkyl = ethyl (dedap) and isopropyl (dipdap)] was studied in the solvents CH3OH and CH3CN. Y1 - 2010 UR - http://www3.interscience.wiley.com/cgi-bin/jhome/4849 U6 - https://doi.org/10.1002/Rcm.4519 SN - 0951-4198 ER - TY - JOUR A1 - Kammer, Stefan A1 - Starke, Ines A1 - Pietrucha, Andreas A1 - Kelling, Alexandra A1 - Mickler, Wulfhard A1 - Schilde, Uwe A1 - Dosche, Carsten A1 - Kleinpeter, Erich A1 - Holdt, Hans-Jürgen T1 - 1,12-Diazaperylene and 2,11-dialkylated-1,12-diazaperylene iridium(III) complexes [Ir((CN)-N-boolean AND)(2)((NN)-N-boolean AND)]PF6: new supramolecular assemblies JF - Dalton transactions : a journal of inorganic chemistry, including bioinorganic, organometallic, and solid-state chemistry N2 - A series of new monocationic iridium(III) complexes [Ir((CN)-N-boolean AND)(2)((NN)-N-boolean AND)]PF6 with "large-surface" alpha,alpha'-diimin ligands (NN)-N-boolean AND (dap = 1,12-diazaperylene, dmedap = 2,11-dimethyl-1,12-diazaperylene, dipdap = 2,11-diisopropyl-1,12-diazaperylene) and different cyclometalating ligands (CN)-N-boolean AND (piq = 1-phenylisoquinoline, bzq = benzo[h]quinoline, ppz = 1-phenylpyrazole, thpy = 2-(2-thienyl)pyridine, ppy = 2-phenylpyridine, meppy = 2-(4-methylphenyl)pyridine, dfppy = 2-(2,4-difluorophenyl)pyridine) were synthesized. The solid structures of the complexes [Ir(piq)(2)(dap)]PF6, [Ir(bzq)(2)(dap)]PF6, [Ir(ppy)(2)(dipdap)]PF6, [Ir(piq)(2)(dmedap)]PF6, [Ir(ppy)(2)(dap)]PF6 and [Ir(ppz)(2)(dap)]PF6 are reported. In [Ir(piq)(2)(dap)]PF6, the dap ligand and one of the piq ligands of each cationic complex are involved in pi-pi stacking interactions forming supramolecular channels running along the crystallographic c axis. In the crystalline [Ir(bzq)(2)(dap)]PF6 pi-pi stacking interactions between the metal complexes lead to the formation of a 2D layer structure. In addition, CH-pi interactions were found in all compounds, which are what stabilizes the solid structure. In particular, a significant number of them were found in [Ir(piq)(2)(dap)]PF6 and [Ir(bzq)(2)(dap)]PF6. The crystal structures of [Ir(ppy)(2)(dipdap)]PF6 and [Ir(ppy)(2)(dmedap)]PF6 are also presented, being the first examples of bis-cyclometalated iridium(III) complexes with phenanthroline-type alpha,alpha'-diimin ligands bearing bulky alkyl groups in the neighbourhood of the N-donor atoms. These ligands implicate a distorted octahedral coordination geometry that in turn destabilized the Ir-N-N boolean AND N bonds. The new iridium (III) complexes are not luminescent. All compounds show an electrochemically irreversible anodic peak between 1.15 and 1.58 V, which is influenced by the different cyclometalated ligands. All of the new complexes show two reversible successive one-electron "large-surface" ligand-centred reductions around -0.70 V and -1.30 V. Electrospray ionisation mass spectrometry (ESI-MS) and collision induced decomposition (CID) measurements were used to investigate the stability of the new complexes. Thereby, the stability agreed well with the order of the Ir-N-N boolean AND N bond lengths. Y1 - 2012 U6 - https://doi.org/10.1039/c2dt30412k SN - 1477-9226 VL - 41 IS - 34 SP - 10219 EP - 10227 PB - Royal Society of Chemistry CY - Cambridge ER -