@article{LaschewskyPoundSkrabaniaetal.2007,
  author    = {Laschewsky, Andr{\´e} and Pound, Gwenaelle and Skrabania, Katja and Holdt, Hans-Joachim and Teller, Joachim},
  title     = {Unsymmetrical bifunctional trithiocarbonate as unexpected by-product in the synthesis of a dithioester RAFT agent},
  issn      = {0303-402X},
  doi       = {10.1007/s.00396-007-1653-5},
  year      = {2007},
  abstract  = {The trithiocarbonate 2-(benzylsulfanylthiocarbonylsulfanyl) propanoic acid is formed as minor by-product in the synthesis of the dithioester 2-((2-phenylthioacetyl)sulfanyl) propanoic acid via the Grignard route. The mechanism for this side reaction is not clear. The isolated trithiocarbonate may act as unsymmetrical but bifunctional RAFT agent in the aqueous polymerization of N,N-dimethyl acrylamide. Therefore, it is important to separate it completely from the dithioester before engaging the latter in controlled free radical polymerization to guarantee a maximum control.},
  language  = {en}
}
@article{RudershausenDrexlerBansseetal.2007,
  author    = {Rudershausen, S. and Drexler, Hans-Joachim and Banße, Wolfgang and Kelling, Alexandra and Schilde, Uwe and Holdt, Hans-Joachim},
  title     = {Three polymorphs of bis(5-methylthio-1,2-dithiole-3-thione)-disulfide},
  doi       = {10.1002/crat.200610776},
  year      = {2007},
  abstract  = {The title compound, bis(5-methylthio-1,2-dithiole-3-thione)-disulfide, was yielded for the first time as by- product of the reaction of nickel(II) and cobalt(II) ions with 5-methylthio-1,2-dithiole-3-thione-4-thiolate. The compound can be obtained directly by oxidation of the ammonium salt of the ligand. C8H6S10 forms three polymorphs: (I), which crystallizes in the orthorhombic space group P212121, (II) and (III), which crystallize in the monoclinic space groups P21/c and P21/n, respectively. The crystal and molecular structures are presented here. The determination of the absolute configuration of (I) indicated the P-helical enantiomer. In contrast to this, the crystals of (II) und (III) are racemic, containing P- and M-helical enantiomers. The polymorphs differ in the kind of skewing around the disulfide bond and of the positions of the both dithiole rings to the S-S-moiety},
  language  = {en}
}
@article{JansenBuschmannWegoetal.2001,
  author    = {Jansen, K. and Buschmann, Hans-J{\"u}rgen and Wego, A. and Dopp, D. and Mayer, C. and Holdt, Hans-Joachim and Schollmeyer, E.},
  title     = {Curcubit[5]uril, decamethylcururbit[5]uril and curcurbit[6]uril : synthesis, solubility and amin complex formation},
  year      = {2001},
  abstract  = {A simple way to prepare cucurbit[5]uril is described. The macrocycles of the cucurbituril type are nearly insoluble in water. The solubilities of cucurbit[5]uril, decamethylcucurbit[5]uril and cucurbit[6]uril in hydrochloric acid, formic acid and acetic acid of different concentrations have been investigated. Due to the formation of complexes between cucurbit[n]urils and protons the solubility increases in aqueous acids. The macrocyclic ligands are able to form complexes with several organic compounds. Thus, the complex formation of the cucurbituril macrocycles with different amines has beenstudied by means of calorimetric titrations. The reaction enthalpy gives noevidence of the formation of inclusion or exclusion complexes. 1H-NMR measurements show that in the case of cucurbit[5]uril and cucurbit[6]uril the organic guest compound is included within the hydrophobic cavity. Decamethylcucurbit[5]uril forms only exclusion complexes with organicamines. This was confirmed by the crystal structure of the decamethylcucurbit[5]uril-1,6- diaminohexane complex. complex formation - cucurbit[5]uril - cucurbit[6]uril - decamethylcucurbit[5]uril - solubility - synthesis},
  language  = {en}
}
@article{GrotjahnLehmannAurichetal.2001,
  author    = {Grotjahn, Manuela and Lehmann, S. and Aurich, Ines and Holdt, Hans-Joachim and Kleinpeter, Erich},
  title     = {NMR spectroscopic and molecular modelling studies of the solution structure and complexational behaviour of some bis(benzocrown ether)s},
  year      = {2001},
  abstract  = {Structural information about the bis(benzo crown ether)s I-VI and their complexes with alkali metal cations was deduced from the 13C NMR chemical shifts, the salt-induced 1H and 13C chemical shifts and the vicinal 1H,1H coupling constants. Especially the isomerism with respect to the amide O=C - NH bonds and imine fragments were assigned by various useful NMR parameters ( C=O, 1JN,H, 1JC,H) and proved to be E,E-anti,anti. Furthermore, stereochemical information about preferred conformations about flexible bonds was obtained from 2D ROESY NMR experiments. The complex formation (2:1 complexes and sandwich-like 1:1 complexes, respectively) were determined also by 23Na NMR spectroscopy. The conformational study of the crown ethers was accompanied and corroborated by molecular dynamics and quantum chemical calculations.},
  language  = {en}
}
@article{SpannenbergBuschmannHoldtetal.1999,
  author    = {Spannenberg, A. and Buschmann, Hans-J{\"u}rgen and Holdt, Hans-Joachim and Schollmeyer, E.},
  title     = {Complex formation of noncyclic, monocyclic and bicyclic ligands with nickel(II) and cobalt(II) in acetonitrile},
  issn      = {0095-8972},
  year      = {1999},
  abstract  = {Equilibrium constants and thermodynamic parameters for the complexation of nickel(II) and cobalt(II) by noncyclic, monocyclic and bicyclic ligands in acetonitrile have been determined by calorimetric titrations. The donor atoms and the ring size of the ligands play an important role for the stabilities of the complexes formed. An increasing number of nitrogen atoms in the crown ether favours complex formation. The number of nitrogen donor atoms of the macro- cyclic ligands examined has a direct influence on the values of the reaction enthalpies. Keywords: Complex formation; crown ethers; azacrown ethers; thiacrown ethers; cryptands; acetonitrile},
  language  = {en}
}