@article{StarkeKochHoldtetal.1995, author = {Starke, Ines and Koch, Andreas and Holdt, Hans-J{\"u}rgen and Kleinpeter, Erich}, title = {1H, 13C, and 15N NMR study of the solution structure of metabridged bis(benzo-15-crown-5-ether)s}, year = {1995}, language = {en} } @article{StarkeKammerGrunwaldetal.2008, author = {Starke, Ines and Kammer, Stefan and Grunwald, Nicolas and Schilde, Uwe and Holdt, Hans-J{\"u}rgen and Kleinpeter, Erich}, title = {Complexation of diazaperylene and bisisoquinoline with transition metal ions in the gas phase studied by electrospray ionization mass spectrometry}, year = {2008}, abstract = {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.}, language = {en} } @article{HoldtMuellerPotteretal.2006, author = {Holdt, Hans-J{\"u}rgen and M{\"u}ller, Holger and Potter, Matthias and Kelling, Alexandra and Schilde, Uwe and Starke, Ines and Heydenreich, Matthias and Kleinpeter, Erich}, title = {The first sandwich complex with an octa(thioether) coordination sphere : Bis(maleonitrile-tetrathia-12-crown- 4)silver(I)}, issn = {1434-1948}, doi = {10.1002/ejic.200501109}, year = {2006}, abstract = {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).}, language = {en} } @article{StarkeFuerstenbergMuelleretal.2006, author = {Starke, Ines and F{\"u}rstenberg, Sylvia and M{\"u}ller, Holger and Holdt, Hans-J{\"u}rgen and Kleinpeter, Erich}, title = {Electrospray mass spectrometric studies of the complexational behavior of maleonitrile thiacrown ethers with various metals}, doi = {10.1002/Rcm.2384}, year = {2006}, abstract = {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}, language = {en} } @article{StarkeKammerHoldtetal.2010, author = {Starke, Ines and Kammer, Stefan and Holdt, Hans-J{\"u}rgen and Kleinpeter, Erich}, title = {Stability of disubstituted copper complexes in the gas phase analyzed by electrospray ionization mass spectrometry}, issn = {0951-4198}, doi = {10.1002/Rcm.4519}, year = {2010}, abstract = {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.}, language = {en} } @article{KammerStarkePietruchaetal.2012, author = {Kammer, Stefan and Starke, Ines and Pietrucha, Andreas and Kelling, Alexandra and Mickler, Wulfhard and Schilde, Uwe and Dosche, Carsten and Kleinpeter, Erich and Holdt, Hans-J{\"u}rgen}, title = {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}, series = {Dalton transactions : a journal of inorganic chemistry, including bioinorganic, organometallic, and solid-state chemistry}, volume = {41}, journal = {Dalton transactions : a journal of inorganic chemistry, including bioinorganic, organometallic, and solid-state chemistry}, number = {34}, publisher = {Royal Society of Chemistry}, address = {Cambridge}, issn = {1477-9226}, doi = {10.1039/c2dt30412k}, pages = {10219 -- 10227}, year = {2012}, abstract = {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.}, language = {en} }