- Visible-Light Promoted C–O Bond Formation with an Integrated Carbon Nitride–Nickel Heterogeneous Photocatalyst
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Ni-deposited mesoporous graphitic carbon nitride (Ni-mpg-CNx) is introduced as an inexpensive, robust, easily synthesizable and recyclable material that functions as an integrated dual photocatalytic system. This material overcomes the need of expensive photosensitizers, organic ligands and additives as well as limitations of catalyst deactivation in the existing photo/Ni dual catalytic cross-coupling reactions. The dual catalytic Ni-mpg-CNx is demonstrated for C–O coupling between aryl halides and aliphatic alcohols under mild condition. The reaction affords the ether product in good-to-excellent yields (60–92 %) with broad substrate scope, including heteroaryl and aryl halides bearing electron-withdrawing, -donating and neutral groups. The heterogeneous Ni-mpg-CNx can be easily recovered from the reaction mixture and reused over multiple cycles without loss of activity. The findings highlight exciting opportunities for dual catalysis promoted by a fully heterogeneous system.
- Vijeta, Arjun,Casadevall, Carla,Roy, Souvik,Reisner, Erwin
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supporting information
p. 8494 - 8499
(2021/03/08)
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- A highly stable all-in-one photocatalyst for aryl etherification: The NiIIembedded covalent organic framework
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The efficient conversion of aryl bromides to the corresponding aryl alkyl ethers by dual nickel/photocatalysis has seen great progress, but difficulties of recycling the photosensitizer or nickel complexes cause problems of sustainability. Here, we report the design of a novel, highly stable vinyl bridge 2D covalent organic framework (COF) containing Ni, which combines the role of photosensitizer and reactive site. The as-prepared sp2c-COFdpy-Ni acts as an efficient heterogeneous photocatalyst for C-O cross coupling. The sp2c-COFdpy-Ni can be completely recovered and used repeatedly without loss of activity, overcoming the limitations of the prior methods. Preliminary studies reveal that strong interlayer electron transfer may facilitate the generation of the proposed intermediate sp2c-COFdpy-NiI in a bimolecular and self-sustained manner. This all-in-one heterogeneous photocatalyst exhibits good compatibility of substrates and tolerance of functional groups. The successful attempt to expand the 2D COFs with this new catalyst into photocatalytic organic transformation opens an avenue for photoredox/transition metal mediated coupling reactions.
- Chen, Hao,Dong, Wenbo,Hu, Jianxiang,Rao, Li,Wang, Pei,Wang, Shengyao,Xiang, Yonggang,Yang, Yi
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p. 5797 - 5805
(2021/08/23)
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- Photorelease of Pyridines Using a Metal-Free Photoremovable Protecting Group
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The photorelease of bioactive molecules has emerged as a valuable tool in biochemistry. Nevertheless, many important bioactive molecules, such as pyridine derivatives, cannot benefit from currently available organic photoremovable protecting groups (PPGs). We found that the inefficient photorelease of pyridines is attributed to intramolecular photoinduced electron transfer (PET) from PPGs to pyridinium ions. To alleviate PET, we rationally designed a strategy to drive the excited state of PPG from S1 to T1 with a heavy atom, and synthesized a new PPG by substitution of the H atom at the 3-position of 7-dietheylamino-coumarin-4-methyl (DEACM) with Br or I. This resulted in an improved photolytic efficiency of the pyridinium ion by hundreds-fold in aqueous solution. The PPG can be applied to various pyridine derivatives. The successful photorelease of a microtubule inhibitor, indibulin, in living cells was demonstrated for the potential application of this strategy in biochemical research.
- Dong, Zaizai,Fang, Xiaohong,Kou, Xiaolong,Tan, Weihong,Tang, Xiao-Jun,Wu, Yayun,Zhang, Zhen,Zhao, Rong,Zhou, Wei
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supporting information
p. 18386 - 18389
(2020/08/24)
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- Ionic Liquids as “Masking” Solvents of the Relative Strength of Bases in Proton Transfer Reactions
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Equilibrium constants for the proton transfer reaction between pyridines and trifluoroacetic acid were measured in room-temperature ionic liquids (ILs) of different cation–anion compositions. The experimental equilibrium constants for ion-pair formation were corrected according to the Fuoss equation. The calculated equilibrium constants for the formation of free ions were taken as a quantitative measure of the base strength in IL solutions and compared with the relative constants in water. The effect of IL composition is discussed for a series of fixed IL anions and fixed IL cations. Finally, the sensitivity of the proton transfer reaction to the electronic effects of the substituent groups on the pyridine ring was quantified by applying the Hammett equation. A more marked levelling effect on the base strength was observed in ILs than in water. The Hammett reaction constants ρ were then correlated with solvent parameters according to a multi-parametric analysis, which showed that both specific hydrogen-bond donor/acceptor and non-specific interactions play an important role, with α and permittivity being the main parameters affecting the ability of the IL to differentiate the strength of the base.
- Zappacosta, Romina,Di Crescenzo, Antonello,Ettorre, Valeria,Fontana, Antonella,Pierini, Marco,Siani, Gabriella
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- Preparation method of cisapride key intermediate
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The invention provides a preparation method of a cisapride key intermediate. The preparation method includes the steps of adopting 3-pyridine as an initial raw material, 3-methoxypyridine is synthesized through nucleophilic substitution, 4-nitryl-3-methoxypyridine is prepared through a nitration reaction, a 4-nitryl-3-methoxyl-N-(3-(4-fluorophenoxy)propyl) quaternized pyridinium is prepared through quaternization, and the cisapride key intermediate, namely (cis)-N-(3-(4-fluorophenoxy)propyl)-4-amino-3-methoxy piperidine, is prepared through catalytic hydrogenation at last. The preparation method has the advantages of being low in cost, easy to operate and the like.
- -
-
Paragraph 0026; 0027; 0032; 0033; 0038; 0039; 0044; 0045
(2019/01/06)
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- Synthesis method of heterocyclic compound 3-methoxypyridine
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The invention discloses a synthesis method of a heterocyclic compound 3-methoxypyridine. The method comprises the following steps: putting raw materials, i.e., 3-halogenated pyridine, hydrogen peroxide and acetic acid into a three-mouth flask, carrying out reaction for 4-8h at the temperature of 40-80 DEG C under the condition of stirring, recovering the acetic acid, adding a saturated sodium carbonate solution and stirring to enable a system to be alkaline, evaporating to remove water, then adding chloroform for washing, and carrying out vacuum distillation to obtain N-oxide-3-halogenated pyridine; respectively adding the N-oxide-3-halogenated pyridine, metal salt of alkyl alcohol, a catalyst A and alcohol into the three-mouth flask, carrying out reflux reaction for 5-8h under the condition of stirring, then cooling, neutralizing a product to be neutral, and carrying out distillation to obtain N-oxide-3-alkyloxypyridine; respectively adding the N-oxide-3-alkyloxypyridine, ferric trichloride, hydrazine hydrate, activated carbon and ethanol into the three-mouth flask, carrying out reaction at the temperature of 70 DEG C for 3h, cooling to room temperature, and carrying out vacuum distillation to obtain the 3-methoxypyridine. The synthesis method is high in intermediate conversion rate, mild in reaction conditions, safe in operation, low in price of raw materials and easy in raw material obtaining, thus being suitable for industrial production.
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- Spectroscopic Studies of the Chan-Lam Amination: A Mechanism-Inspired Solution to Boronic Ester Reactivity
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We report an investigation of the Chan-Lam amination reaction. A combination of spectroscopy, computational modeling, and crystallography has identified the structures of key intermediates and allowed a complete mechanistic description to be presented, including off-cycle inhibitory processes, the source of amine and organoboron reactivity issues, and the origin of competing oxidation/protodeboronation side reactions. Identification of key mechanistic events has allowed the development of a simple solution to these issues: manipulating Cu(I) → Cu(II) oxidation and exploiting three synergistic roles of boric acid has allowed the development of a general catalytic Chan-Lam amination, overcoming long-standing and unsolved amine and organoboron limitations of this valuable transformation.
- Vantourout, Julien C.,Miras, Haralampos N.,Isidro-Llobet, Albert,Sproules, Stephen,Watson, Allan J. B.
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supporting information
p. 4769 - 4779
(2017/04/11)
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- On the absolute photoionization cross section and dissociative photoionization of cyclopropenylidene
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We report the determination of the absolute photoionization cross section of cyclopropenylidene, c-C3H2, and the heat of formation of the C3H radical and ion derived by the dissociative ionization of the carbene. Vacuum ultraviolet (VUV) synchrotron radiation as provided by the Swiss Light Source and imaging photoelectron photoion coincidence (iPEPICO) were employed. Cyclopropenylidene was generated by pyrolysis of a quadricyclane precursor in a 1 : 1 ratio with benzene, which enabled us to derive the carbene's near threshold absolute photoionization cross section from the photoionization yield of the two pyrolysis products and the known cross section of benzene. The cross section at 9.5 eV, for example, was determined to be 4.5 ± 1.4 Mb. Upon dissociative ionization the carbene decomposes by hydrogen atom loss to the linear isomer of C3H+. The appearance energy for this process was determined to be AE0K(c-C3H2; l-C3H+) = 13.67 ± 0.10 eV. The heat of formation of neutral and cationic C3H was derived from this value via a thermochemical cycle as ΔfH0K(C3H) = 725 ± 25 kJ mol-1 and ΔfH0K(C3H+) = 1604 ± 19 kJ mol-1, using a previously reported ionization energy of C3H.
- Holzmeier, Fabian,Fischer, Ingo,Kiendl, Benjamin,Krueger, Anke,Bodi, Andras,Hemberger, Patrick
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p. 9240 - 9247
(2016/04/09)
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- A closer look at the bromine-lithium exchange with tert-butyllithium in an aryl sulfonamide synthesis
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A practical protocol for the one-pot synthesis of various aryl sulfonamides, notably of pyridine-core-substituted 7-azaindolyl sulfonamides, is described. A key step is the well-known bromine-lithium exchange reaction of an aryl bromide with tert-butyllithium (t-BuLi). Differing from the common practice to use 2 or more equiv of organolithium, the exact amount of t-BuLi needed for a sufficient exchange reaction is determined for each aryl bromide in a GC-MS-assisted experiment.
- Waldmann, Christopher,Schober, Otmar,Haufe, Guenter,Kopka, Klaus
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supporting information
p. 2954 - 2957
(2013/07/26)
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- A convenient and practical synthesis of anisoles and deuterated anisoles by palladium-catalyzed coupling reactions of aryl bromides and chlorides
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Synthesis of anisole: Aryl and heteroaryl halides undergo selective C-O cross-coupling reactions with methanol in the presence of a Pd(OAc) 2/L3 catalyst system. The corresponding ethers were obtained under mild conditions in good yields. The catalytic methodology was also used for the synthesis of labeled deuterated anisoles in good yields (see scheme). Copyright
- Gowrisankar, Saravanan,Neumann, Helfried,Beller, Matthias
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supporting information; experimental part
p. 2498 - 2502
(2012/03/27)
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- Basicity of pyridine and some substituted pyridines in ionic liquids
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Figure presented The equilibrium constants for ion pair formation of some pyridines have been evaluated by spectrophotometric titration with trifluoroacetic acid in different ionic liquids. The basicity order is the same in ionic liquids and in water. The substituent effect on the equilibrium constant has been discussed in terms of the Hammett equation. Pyridine basicity appears to be less sensitive to the substituent effect in ionic liquids than in water.
- Angelini, Guido,De Maria, Paolo,Chiappe, Cinzia,Fontana, Antonella,Pierini, Marco,Siani, Gabriella
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experimental part
p. 3912 - 3915
(2010/08/06)
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- Streamlined synthesis of the bippyphos family of ligands and cross-coupling applications
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We describe the efficient preparation of Bippyphos, 1. The key precursor to Bippyphos, 5, was prepared via a one-pot bromination of diketone 2 followed by alkylation with pyrazole and condensation with phenylhydrazine. Lithiation of 5 and trapping with ditert-butylchlorophosphine afforded Bippyphos, 1. Using this approach we have prepared several derivatives of Bippyphos to probe the structure and activity relationships of this family of phosphine ligands. We also demonstrate the utility of these ligands in Pdcatalyzed amination reactions and other cross-coupling reactions.
- Withbroe, Gregory J.,Singer, Robert A.,Sieser, Janice E.
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p. 480 - 489
(2013/01/03)
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- Barrierless electron transfer bond fragmentation reactions
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The ultrafast N-O bond fragmentation in a series of N-methoxypyridyl radicals, formed by one-electron reduction of the corresponding N-methoxypyridiniums, has been investigated as potentially barrierless electron-transfer-initiated chemical reactions. A model for the reaction involving the electronic and geometric factors that control the shape of the potential energy surface for the reaction is described. On the basis of this model, molecular structural features appropriate for ultrafast reactivity are proposed. Femtosecond kinetic measurements on these reactions are consistent with a kinetic definition of an essentially barrierless reaction, i.e., that the lifetime of the radical is a few vibrational periods of the fragmenting bond, for the p-methoxy-N-methoxypyridyl radical.
- Lorance, Edward D.,Kramer, Wolfgang H.,Gould, Ian R.
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p. 14071 - 14078
(2007/10/03)
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- Etherification of heterocyclic compounds by nucleophilic aromatic substitutions under green chemistry conditions
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Solid-liquid phase transfer catalysis coupled with microwave irradiation was shown to be an efficient method for SNAr reaction of halogenated quinoline and pyridine with alkoxides and phenoxides. Whereas for phenoxylation there is no need for any solvent, the addition of small amount of non-polar solvent is necessary during methoxylation for accurate monitoring of temperatures. Yields and conditions involved here constitute a noticeable improvement over classical methods within the frame of Green Chemistry. Specific MW effects were evidenced for phenoxylation and interpreted in terms of late position of the transition state along the reaction coordinates.
- Lloung, Matthieu,Loupy, André,Marque, Sylvain,Petit, Alain
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p. 297 - 308
(2007/10/03)
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- An Efficient Deoxgenation of Heteroaromatic N-Oxides Using Zinc Dust/Ammonium Formate Reagent System
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Heteroaromatic N-oxides were readily and selectively deoxygenated to the corresponding bases with zinc/ammonium formate reagent system.
- Balicki, Roman,Cybulski, Marcin,Maciejewski, Grzegorz
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p. 4137 - 4141
(2007/10/03)
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- A mild and selective deoxygenation of N-oxides with ammonium formate as a catalytic hydrogen transfer agent
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Ammonium formate catalytic transfer hydrogenation in the presence of raney nickel has shown utility for mild and selective deoxygenation of heteroaromatic N-oxides in neutral medium.
- Balicki, Roman,Maciejewski, Grzegorz
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p. 1681 - 1683
(2007/10/03)
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- Effect of neutral pyridine leaving groups on the mechanisms of influenza type A viral sialidase-catalyzed and spontaneous hydrolysis reactions of α-D-N-acetylneuraminides
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A reagent panel, comprised of five pyridinium salts of α-D-N-acetylneuraminic acid, was synthesized and then used to probe enzymatic (α-sialidase) and nonenzymatic mechanisms of neuraminide hydrolysis. Spontaneous hydrolysis of the pyridinium salts proceeded via two independent pathways, where unassisted C-N bond cleavage was the rate-determining step. Cationic species (i.e., anomeric carboxylate protonated) displayed apparent pK(a) values in the range of 0.4-0.7. However, spontaneous hydrolyses of the cationic and zwitterionic species had similar β(1g) values of -1.22 ± 0.16 and -1.22 ± 0.07, respectively. The results, plus the activation parameters calculated from the hydrolysis of pyridinium α-D-N-acetylneuraminide (ΔH(+) = 112 ± 2 kJ mol-1 and ΔS(+) = 28 ± 4 J mol-1 K-1), strongly suggest that the anomeric carboxylate does not assist in the departure of neutral pyridine leaving groups. Enzymatic hydrolysis was studied using an influenza viral α-sialidase (A/Tokyo/3/67) which was recombinantly expressed using a baculovirus/insect cell expression system. Sialidase protein was purified by a combination of density gradient centrifugation and gel filtration chromatography. Kinetic parameters for the enzymatic hydrolysis of the pyridinium salts were measured at 37 °C and at pH values of 6.0 and 9.5. The β(1g) values derived for k(cat)/K(m) and k(cat) were essentially zero, indicating that chemical transformations/events are not rate-determining. Rather, this observation is consistent with a model for α-sialidase-catalyzed hydrolyses (Guo, X.; Laver, W. G.; Vimr, E.; Sinnott, M. L., J. Am. Chem. Soc. 1994, 116, 5572) in which k(cat)/K(m) is determined by a conformational change of the first-formed Michaelis complex and k(cat) is determined by the virtual transition state made up of two separate conformational events.
- Chou, Doug T. H.,Watson, Jacqueline N.,Scholte, Andrew A.,Borgford, Thor J.,Bennet, Andrew J.
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p. 8357 - 8364
(2007/10/03)
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- An efficient and chemoselective deoxygenation of hetero cyclic N-oxides using LiCl/NaBH4
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A practical and novel reagent system LiCl/NaBH4 is used for the deoxygenation of N-Oxides to amines is described.
- Raja Ram,Purushothama Chary,Iyengar
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p. 3511 - 3515
(2007/10/03)
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- A mild deoxygenation of heteroaromatic N-oxides by formamidinesulfinic acid
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Various heteroaromatic N-oxides were efficiently deoxygenated to the corresponding bases under mild conditions using formamidinesulfinic acid (thiourea S,S-dioxide).
- Balicki, Roman,Chmielowiec, Urszula
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p. 1105 - 1107
(2007/10/03)
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- New methods of preparing cyclopentenone ketals: The photosolvolysis of 3-alkoxypyridinium tetrafluoroborates
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A new base catalysed method of ketal formation is reported, such that substituted cyclopentenone ketals are prepared from 3-alkoxypyridinium tetrafluoroborate salts.
- Penkett,Simpson
-
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- Photosolvolysis reactions of 3-alkoxypyridinium tetrafluoroborate salts
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Irradiation of a series of 3-alkoxypyridinium tetrafluoroborate salts in alcohol solution resulted in the formation of cyclopentenone ketals by diastereoselective incorporation of the alcohol solvent under the basic conditions of the photolysis reaction. In a second series of photochemical reactions, the same 3-alkoxypyridinium salts were irradiated in water to yield β-hydroxycyclopentanones stereoselectively.
- Penkett, Clive S.,Simpson, Iain D.
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p. 6183 - 6204
(2007/10/03)
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- A Novel and Efficient Deoxygenation of Hetero Cyclic N-Oxides Using ZrCl4/NaBH4
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A practical and novel reagent system ZrCl4/NaBH4 is used for the deoxygenation of N-Oxides to amines is described.
- Chary, K. Purushothama,Mohan, G. Hari,Iyengar, D. S.
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p. 1339 - 1340
(2007/10/03)
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- Synthesis of alkyl heteryl ethers from acetates under interphase catalysis conditions in a liquid/solid system
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The reaction of acetates of heterocyclic alcohols with alkyl halides in the two-phase catalytic system of solid KOH/C6H6/18-crown-6 at room temperature leads selectively to the formation of the corresponding heterocyclic ethers in 32-93% yield. 1998 Plenum Publishing Corporation.
- Abele,Abele,Gaukhman,Lukevics
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- N.C.A. 11C-labelled of benzoid compounds in ring positions:[11C]anisole derivatives
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The synthesis route to n.c.a. 3-nitro-[3-11C]]anisole (3) by use of the principle of synchronous six-electron cyclization of hexatriene systems into aromatics is described and discussed. Nitro-[11C]methane (1) reacts with the prepared precursor 5-dimethylamino-2-methoxy-penta-2,4-dienylidene-1- dimethylammonium tetranuoroborate (2b) in the presence of BuLi to form 1-dimethyl-amino-4-methoxy-6-nitro-[6-11C] hexatriene (IA, IB), followed by cyclization/ aromatization into 3. Starting from 1, 3-nitro-[311C]]anisole of a radiochemical purity of about 65% and a mean specific radioactivity of 1 Ci/μmol was obtained within 10 min. Related to [11C]CH3NO2, the reproducible radiochemical yield of 3 (decay-conected) was 60 ± 5 %. Reduction of 3 by heating the above reaction mixture with aqueous Na2S gave 3-amino-[3-11C]anisole (4) of a radiochemical purity of about 50 %. The reproducible radiochemical yield of 4 (decay-corrected) in relation to 1 was 45 ± 5 %, the synthesis time from 1 was 16 min.
- Maeding,Steinbach,Johannsen
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p. 585 - 601
(2007/10/03)
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- SIMPLE AND CONVENIENT DEOXYGENATION OF HETEROAROMATIC N-OXIDES WITH SODIUM HYPOPHOSPHITE
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Sodium hypophosphite catalytic transfer hydrogenation in the presence of 10percent palladium on carbon constitutes a simple and excellent deoxygenation method for heteroaromatic N-oxides in acetic acid medium.
- Balicki, Roman,Kaczmarek, Lukasz
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p. 385 - 386
(2007/10/02)
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- Deoxydative Thiation of 3-Substituted Pyridine N-Oxides with 4-Methoxytoluene-α-thiol: A Divergent Route to Pyridinethiols
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Synthesis of 3-substituted 2-pyridinethiols was achieved by thiation of pyridine N-oxides with 4-methoxytoluene-α-thiol in the presence of diethylcarbamoyl chloride followed by cleavage of the resulting sulfides.The case of substitution was shown to be affected by nucleophilicity of the N-oxide oxygen.Addition of zinc bromide to the reaction, a need for triethylamine, decreased most of the yield for thiation products but the formation of 3-methoxy-2-methoxybenzylthiopyridine was only improved.A plausible mechanism of the substitution, particularly β-thiation to the N-oxide function, is discussed compared with the regiochemistry observed in the reaction with diethoxyphosphoryl chloride instead of diethylcarbamoyl chloride.The debenzylation to pyridinethiol was also found to be dependent on the electron-density in the pyridine ring.
- Sato, Nobuhiro,Nagano, Eiichi
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p. 691 - 698
(2007/10/02)
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- Copper(I) Halide Catalysed Synthesis of Alkyl Aryl and Alkyl Heteroaryl Ethers
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A number of alkyl aryl and alkyl heteroaryl ethers have been prepared from (hetero) aryl halides (mainly bromides) and sodium alkoxides, using copper(I)bromide as a catalyst.The influence of the main solvent, the halogen atom, reaction temperature and the presence of oxygen upon the rate and selectivity has been studied.Furthermore the decomposition of the catalyst and the reduction of the aryl halide are studied.
- Keegstra, Menno A.,Peters, Theo H. A.,Brandsma, Lambert
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p. 3633 - 3652
(2007/10/02)
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- A New Diene, 2-Methoxy-1,3-pentadiene-5-ol. Synthesis and Intramolecular Diels-Alder Reactions.
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Reactions of the diene 1-benzyloxy-2-methoxy-1,3-pentadiene-5-ol in intramolecular Diels-Alder reactions using maleic anhydride or fumaric acid ethyl ester is described.The new reactive diene is prepared starting from 3-methoxypyridine.The structure of the diene was elucidated by NOE nmr experiment.
- Joergensen, Tine,Nielsen, Helle Chris,Malhotra, Nageshwar,Becher, Jan,Begtrup, Mikael
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p. 1841 - 1845
(2007/10/02)
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- Efficient Deoxygenation of Heteroaromatic N-Oxides with Ammonium Formate as a Catalytic Hydrogen Transfer Agent
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Ammonium formate catalytic transfer hydrogenation in the presence of 10percent palladium on carbon has shown utility for mild and excellent deoxygenation of heteroaromatic N-oxides in neutral medium.
- Balicki, Roman
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p. 645 - 646
(2007/10/02)
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- ORTHO LITHIATION OF 2-, 3-, AND 4-METHOXYPYRIDINES
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The ortho lithiation of 2-, 3-, and 4-methoxypyridine was effected using mesityllithium as the metalating base.
- Comins, Daniel L.,LaMunyon, Donald H.
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p. 773 - 776
(2007/10/02)
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- Synthesis and Properties of 2,2'-Bipyridin-3-ols and -3,3'-diols
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The synthesis of the 2-furyl ketones 5-7 and 13 and their reaction with ammonium acetate in boiling acetic acid to 3-substituted 2,2'-bipyridines and to 2-(2-pyrimidinyl)-3-pyridinol (14) via a ring-transformation reaction are described.Strong intramolecular hydrogen bonds are responsible for their physical and chemical properties.
- Siemanowski, Werner,Witzel, Herbert
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p. 1731 - 1739
(2007/10/02)
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- A Simple Synthesis of 3-Methoxypyridine and of Analogues by Alkylation Reactions
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Solid potassium hydroxide in dimethylsulfoxide has high basicity but only low nucleophilicity and is used as a base for the methylation of 3-hydroxypyridine (1) and of analogues with methyl iodide.The reaction is not interferred by the addition of small amounts of water and gives yields of 40 percent for the reaction of 1 and up to 100 percent for analogues.The described reagent therefore may be an alternative to lithium diisopropylamide.
- Finkentey, Christel,Langhals, Elke,Langhals, Heinz
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p. 2394 - 2397
(2007/10/02)
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