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1	Author	Walter Strohmeier, Erich Hitzel	Requires cookie*
	Title	Katalytische Aktivität von homogenem und heterogenisiertem RhCl(PPh3)3 für die Hydrierung von Substraten ohne Solvens Catalytic Activity of Homogeneous and Heterogenized RhCl(PPh3)3 for Hydrogenation of Substrates without Solvents
	Reference	(Z. Naturforsch. 31b, 945—947 [1976]; eingegangen am 2. März 1976)
	Published	1976
	Keywords	Catalysis, Hydrogenation, Rhodium
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	TEI-XML for	default:Reihe_B/31/ZNB-1976-31b-0945.pdf
	Identifier	ZNB-1976-31b-0945
	Volume	31

2	Author	Valerie Bertagna, Francis Rouelle, Marius Chemla	Requires cookie*
	Title	Copper Contamination Mechanism of Silicon Substrates from HF Solutions
	Abstract	The contamination of silicon wafers from dilute HF solutions containing ultratrace levels of metallic ion impurities is a subject of constant interest. The mechanism of copper electroless deposition from HF onto monocrystalline silicon was investigated using a new electrochemical cell, which proved to be a very sensitive detector for in situ characterization of silicon surfaces. Upon addition of copper trace amounts, the open-circuit potential was observed to shift rapidly towards more positive values at a rate nearly proportional to the copper concentration. All poten-tial/time curves tend to reach a limiting value of the potential, while quantitative measurements of radioactive tracers revealed that during a few tens of minutes, copper ions were continuously reduced on the silicon surface. Electrochemical potentials and voltammetric measurements were interpreted in terms of the mixed potential theory and led to the conclusion that copper nuclei act as a catalyst which enhances the cathodic activity for protons reduction. The model was supported by AFM observations which demonstrated the initiation of corrosion pits around the nuclei.
	Reference	Z. Naturforsch. 52a, 465—176 (1997); received April 14 1997
	Published	1997
	Keywords	Silicon, contamination, copper, catalysis
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	TEI-XML for	default:Reihe_A/52/ZNA-1997-52a-0465.pdf
	Identifier	ZNA-1997-52a-0465
	Volume	52

3	Author		Requires cookie*
	Title	Catalytic Hydrogenation of U nsaturated Compounds with H 2PtC l6-SnCl2 * 2 H ,0 in Acetic Acid
	Abstract	W a l t e k S t r o h m e ie r und M a g d a le n a P f ö h l e r A hydrogenation catalyst, operating under mild conditions can be prepared by dissolving H 2PtC l6 and SnCl2 • 2 H 20 in acetic acid. After injection of an unsaturated compound under a H 2-atmosphere the active m oiety of the catalyst is generated. No active m oiety of catalyst is formed if the compound has a triple bond. But acetylenic derivatives are hydrogenated if the active m oiety of the catalyst is first produced by hydrogenation of cyclohexene.
	Reference	(Z. Naturforsch. 30b, 466—467 [1975]; eingegangen am 27. Januar 1975)
	Published	1975
	Keywords	Catalysis, Hydrogenation, Unsaturated Compounds
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	TEI-XML for	default:Reihe_B/30/ZNB-1975-30b-0466_n.pdf
	Identifier	ZNB-1975-30b-0466_n
	Volume	30

4	Author	Walter Strohmeier, Luise Weigelt	Requires cookie*
	Title	Homogeneous Catalytic Hydrogenation of Unsaturated Compounds with H2PtCl6 + SnCl2 * 2 H20 in iso-Propanol
	Abstract	A catalytical system for homogeneous hy-drogenation of unsaturated compounds, oper-ating under mild conditions can be prepared with H2PtCl6-SnCl2 • 2 H20 and the additives HBr and H20 in m>-propanol. Reaction rates up to 32 mMol • 1 _1 • min -1 were observed. After hydrogenation of one batch new sub-strate can be injected several times without noticeable desactivation of the system. Hy-drogenation rate of 2-tr-cis-hexene is only 0,5 times less than of 1-hexene. Mesityloxide is selectively hydrogenated regarding the double bond.
	Reference	(Z. Naturforsch. 31b, 387—389 [1976]; eingegangen am 17. Oktober 1975)
	Published	1976
	Keywords	Catalysis, Hydrogenation, Unsaturated Compounds
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	TEI-XML for	default:Reihe_B/31/ZNB-1976-31b-0387_n.pdf
	Identifier	ZNB-1976-31b-0387_n
	Volume	31

5	Author	Walter Strohmeier, Magdalena Pföhler	Requires cookie*
	Title	Homogeneous and Heterogeneous Catalytic Hydrogenation of Unsaturated Compounds with H2PtCl6 + SnCl2 * 2 H20 in Acetic Acid
	Abstract	The hydrogenation catalyst, prepared by dissolving H2PtCl6 + SnCl2 • 2 H20 in acetic acid operates as a homogeneous or heteroge-neous catalyst, depending on the ratio v = Sn/Pt. Styrene is hydrogenated by the homo-geneous and heterogeneous system but cyclo-hexene only by the heterogeneous system.
	Reference	(Z. Naturforsch. 31b, 390—392 [1976]; eingegangen am 17. Oktober/24. November 1975)
	Published	1976
	Keywords	Catalysis, Hydrogenation, Unsaturated Compounds
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	TEI-XML for	default:Reihe_B/31/ZNB-1976-31b-0390_n.pdf
	Identifier	ZNB-1976-31b-0390_n
	Volume	31

6	Author	Erich Hitzel	Requires cookie*
	Title	Abbau von Induktionsperioden und Steigerung der Aktivität homogener Hydrierungskatalysatoren mit Iridium als Zentralatom Reduction of Induction Periods and Increase of Activity of Homogenous Iridium Hydrogenation Catalysts
	Abstract	With complexes of iridium as catalysts, induction periods are typical for homogeneous hydrogenation of olefins in bulk. The induction period decreases, as a rule with increasing activity, at higher temperatures and may be suppressed with dibenzoylperoxide, azo-bisisobutyrodinitrile, tetrachloro-l,4-benzoquinone or by preactivation. Triethylamin and SnCl2 • 2H2O are unsuitable additives. The operation "preactivation" leads additionally to great substrate/catalyst-turnover numbers.
	Reference	Z. Naturforsch. 33b, 997—1000 (1978); eingegangen am 19. Juni 1978
	Published	1978
	Keywords	Catalysis, Hydrogenation, Induction Periods, Activity
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	TEI-XML for	default:Reihe_B/33/ZNB-1978-33b-0997.pdf
	Identifier	ZNB-1978-33b-0997
	Volume	33

7	Author	Walter Strohmeier, Johannes-Peter Stasch	Requires cookie*
	Title	Photoaktivierung und Photosensibilisierung des homogenen Hy drierungs -Katalysators IrCl(CO) [P(i-C3H7)3] 2 Photoactivation and Photosensitization of the Homogeneous Hydrogenation Catalyst IrCl(CO)[P(i-C3H7)3]2
	Abstract	Under irradiation with monochromatic light of X < 407 nm homogeneous hydrogenation of acrylic ethvlester with the catalyst IrCl(CO)[P"(i-C3H7)3]2 is much faster than in the dark reaction. Not the catalyst but the hydrido-complex is photochemically activated. With the sensitizer pentacene, photoactivation occurrs with visible light of X < 578 nm already.
	Reference	Z. Naturforsch. 34b, 755—758 (1979); eingegangen am 31. Januar 1979
	Published	1979
	Keywords	Photoactivation, Photosensitization, Hydrogenation, Catalysis
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	TEI-XML for	default:Reihe_B/34/ZNB-1979-34b-0755_n.pdf
	Identifier	ZNB-1979-34b-0755_n
	Volume	34

8	Author	Henri Brunner, Bernd Haßler	Requires cookie*
	Title	Enantioselective Catalysis, 122 [1] Synthesis of New Optically Active 3.5-DinitrosalicyloxazoIines
	Abstract	New optically active 3,5-dinitrosalicyloxazo-lines, derived from 3,5-dinitrosalicylonitrile and the chiral aminodiols (lS,2S)-(+)-2-am ino-l-phe-nyl-l,3-propanediol, (2S)-(-)-2-amino-l,l,4,4-te-traphenyl-l,4-butanediol and (2S)-(-)-2-amino-l,l-diphenyl-l,3-butanediol, were prepared and used as in situ catalysts for enantioselective cyclo-propanation reactions.
	Reference	(Z. Naturforsch. 53b, 126—128 [1998]; eingegangen am 27. O ktober 1997 3.)
	Published	1998
	Keywords	5-Dinitrosalicyloxazolines, Enantioselectivity, Catalysis, Cyclopropanations
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	TEI-XML for	default:Reihe_B/53/ZNB-1998-53b-0126_n.pdf
	Identifier	ZNB-1998-53b-0126_n
	Volume	53

9	Author	Henri Brunner, Bernd Haßler	Requires cookie*
	Title	Enantioselective Catalysis, 120 [1] New Optically Active Pyrrole-oxazolines
	Abstract	14 new optically active pyrrole-oxazolines were synthesised from 2-pyrrole-carbonitrile or methyl 2-pyrrole-carboximidate and chiral amino alcohols. Their use in copper-catalysed enan tioselective cyclopropanation reactions gave only low optical yields (3-14%ee).
	Reference	Z. Naturforsch. 53b, 476—480 (1998); received January 12 1998
	Published	1998
	Keywords	Pyrrole-oxazolines, Enantioselectivity, Catalysis, Cyclopropanations
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	TEI-XML for	default:Reihe_B/53/ZNB-1998-53b-0476.pdf
	Identifier	ZNB-1998-53b-0476
	Volume	53

10	Author	J. M. Ramallo-López, F. G. Requejo, A. G. Bibiloni, M. Rentería, L. Gutierrez, E. E. Miró	Requires cookie*
	Title	Combined TDPAC and EXAFS Study of InPt/FER Catalysts
	Abstract	Time Differential Perturbed Angular Correlation (TDPAC) experiments using 111 In as probe were performed in order to determine the nature of In-sites in In-ferrierite (In/FER), before and after the incorporation of Pt through the hyperfine interaction between the nuclear quadrupole moment of the probe's nucleus and the extranuclear electric field gradient (EFG). Extended X-ray Absorption Fine Structure (EXAFS) measurements were performed to measure the absorbance above the Pt's L m absorption edge in the transmission mode in order to determine the local environment of Pt atoms in Pt/FER and InPt/FER catalysts. TDPAC spectra of 111 In in In/FER and InPt/FER taken at 500°C in air indicated that there are no changes in the indium surroundings after the incorporation of Pt. Three sites were found for indium in both samples. Two of them correspond to the two sites of indium in ln 2 0 3 and the third one is attributed to In in exchange sites of the zeolites. Their population, quadrupole frequencies and asymmetry parameters didn't change with the incorporation of Pt. EXAFS experiments showed similar near neighborhood Pt-0 distances and Pt coordination number in Pt/FER and InPt/FER samples. There is no evidence of the presence of any In-Pt bimetallic entity in InPt/FER catalyst.
	Reference	Z. Naturforsch. 55a, 327—330 (2000); received August 26 1999
	Published	2000
	Keywords	Hyperfine Interactions, TDPAC, EXAFS, Catalysis, Ferrierite
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	TEI-XML for	default:Reihe_A/55/ZNA-2000-55a-0327.pdf
	Identifier	ZNA-2000-55a-0327
	Volume	55

11	Author	Walter Strohmeier, Magdalena Pföhler	Requires cookie*
	Title	Vergleich der Hydrierung ungesättigter Verbindungen mit einem homogenen und heterogenen Platin-Katalysator in Essigsäure Comparison of Hydrogenation of Unsaturated Compounds with a Homogeneous and Heterogeneous Platinum Catalyst in Acetic Acid
	Abstract	Catalytical hydrogenation of unsaturated compounds in acetic acid with the homo-geneous catalyst prepared from H2PtCl6 + SnCl2 • 2 H20 and the heterogeneous catalyst, prepared from H2PtCl6 and H2, were carried out. A comparison of the results reveals two types of substrates, some are readily hydrogenated by the homogeneous the other ones by the heterogeneous system. Turnover numbers up to 1500 were observed. With the heterogeneous catalyst ethylbenzene is hydrogenated to ethylcyclohexane under mild conditions.
	Reference	(Z. Naturforsch. 31b, 941—944 [1976]; eingegangen am 2. März 1976)
	Published	1976
	Keywords	Catalysis, Hydrogenation, Homogeneous Catalyst, Heterogeneous Catalyst
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	TEI-XML for	default:Reihe_B/31/ZNB-1976-31b-0941.pdf
	Identifier	ZNB-1976-31b-0941
	Volume	31

12	Author	Walter Strohmeier, Manfred Michel, Luise Weigelt	Requires cookie*
	Title	mit homogenen Ir-und Ru-Katalysatoren Selective Bulk-Hydrogenation of a,ß Unsaturated Ketones to Ketones with Homogeneous Ir and Ru Catalysts
	Abstract	a,ß Unsaturated ketones are selectively hydrogenated to ketones in homogeneous bulk-catalysis under mild conditions by iridium-and ruthenium complexes. The range of mean turnover is from 6 to 196 depending on substrate, catalyst and reaction conditions. Selectivity ketone/alcohol depends on the degree of conversion and exceeds 100 on con-version of 90%. Einleitende Bemerkungen
	Reference	Z. Naturforsch. 35b, 648—650 (1980); eingegangen am 7. Dezember 1979
	Published	1980
	Keywords	Catalysis, Homogeneous, Selective, Hydrogenation, Unsaturated Ketones
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	TEI-XML for	default:Reihe_B/35/ZNB-1980-35b-0648.pdf
	Identifier	ZNB-1980-35b-0648
	Volume	35

13	Author	WolfgangK. Läuia, Susanne Schoger2, Martin Niegerb	Requires cookie*
	Title	Synthesis and Crystal Structure of Perhydro-l,4-benzoxazino[2,3-n]phenoxazine
	Abstract	The oxidation of fra«s-2-aminocyclohexanol with nitrobenzene in the presence of catalytic amounts of iron inter alia yields perhydro-l,4-benzoxazino[2,3-n]phenoxazine (1). This com pound has been characterized analytically, spectroscopically and by X-ray diffraction. It is postulated that the oxidation of the 2-aminoalcohol leads to the intermediate formation of a 1,2-dione. The direct synthesis of 1 from trans-2-aminocyclohexanol and 1,2-cyclohexandione supports this hypothesis.
	Reference	Z. Naturforsch. 52b, 801—804 (1997); eingegangen am 14. Oktober 1996
	Published	1997
	Keywords	Nitrobenzene, Reduction, Aniline, 2-Aminoalcohols, Catalysis
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	TEI-XML for	default:Reihe_B/52/ZNB-1997-52b-0801.pdf
	Identifier	ZNB-1997-52b-0801
	Volume	52

14	Author	M. Fernanda, N. N. Carvalho3, ArmandoJ L Pombeiro3, Gabriele Wagner3, Bj0m Pedersenb, Rudolf Herrmann	Requires cookie*
	Title	Cascade Reaction of Camphor-Derived Diynes with Transition Metal Compounds
	Abstract	Platinum(II) catalyzes the isomerization o f camphor sulfonamide diynes in a cascade reaction involving annulation o f a five-membered ring to the camphor skeleton, ring-enlargement by C-C bond cleavage, reduction o f sulfur(VI) to sulfur(IV), and oxidation o f a hydroxy group to a ketone. The reactions o f the diynes with other transition metal compounds were also studied. Copper, gold and rhenium give final products similar to those obtained with simple Br0nsted acids or halogens, mainly by annulation o f a five-membered ring to the camphor moiety, accompanied by reduction o f a sulfonamide to a sulfinamide group, but lacking the ring-enlargement step. Palladium(II) occupies an intermediate position as both types o f products are obtained. The reaction mechanism and intermediates are discussed.
	Reference	Z. Naturforsch. 54b, 725—733 (1999); received March 18 1999
	Published	1999
	Keywords	Camphor Diyne, Ring Enlargement, Transition Metals, Catalysis, Alkyne
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	TEI-XML for	default:Reihe_B/54/ZNB-1999-54b-0725.pdf
	Identifier	ZNB-1999-54b-0725
	Volume	54

15	Author	Christian Egger, Ulrich Schubert	Requires cookie*
	Title	Metallkomplexe in Anorganischen Matrices, 5 [1] Katalytische Silanoxidation an einem heterogenisierten Rhodium-Komplex M etal Complexes in Inorganic Matrices, 5 [1] Catalytic Silane Oxidation at a Heterogenized Rhodium Complex
	Abstract	A heterogenized rhodium complex, prepared by sol-gel processing of Rh(CO)Cl[PPh2C H 2C H 2Si(OEt)3]2 and Si(OEt)4, is shown to catalyze the conversion of the si lanes H4_"SiPh" (n = 1 -3) or (H M e2Si)20 to (poly)siloxanes by air or water. Using T H F as a solvent, the silanoles Ph3SiOH or Ph2Si(OH)2 are obtained instead. The reaction of phenyl-acetic acid or acetic acid with HSiPh3 to give silyl esters is catalyzed by the same com pound.
	Reference	Z. Naturforsch. 46b, 783—788 (1991); eingegangen am 14. Januar 1991
	Published	1991
	Keywords	Heterogenized Rhodium Complex, Catalysis, Silanes, Silanoles, Siloxanes, Silyl Esters
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	TEI-XML for	default:Reihe_B/46/ZNB-1991-46b-0783.pdf
	Identifier	ZNB-1991-46b-0783
	Volume	46

16	Author	Stephan Pitter, EckhardD. Injus, Beate Jung, H. Elm, Ar Görls	Requires cookie*
	Title	Phosphinoalkylnitrile: Synthese und Koordinationsverhalten an Palladiumzentren Phosphinoalkylnitnles: Synthesis and Coordination Behaviour at Palladium C entres
	Abstract	Phosphinoalkylnitriles R2P-(CH2)"-CN {R = isopropyl ('pr), phenyl (ph), cyclohexyl (' hex), n -3, 6, 10} have been prepared starting from the corresponding secondary phosphines in an easy three step synthesis. All new compounds were characterized by their 'H -, i3C and 31P NMR data. Some of these new P, N ligands were used to prepare complexes [{R2P-(CH2)"-CN}2PdCl2] which were also identified by their NMR data. In addition the crystal structures of three derivatives, [{'pr2P-(CH2)3-CN }2PdCl2] 7a, [{ph2P-(CH2)3-CN }2PdCl2) 7b and [{ph2P-(CH 2)6-CN}2PdCl2] 8b were determined by X-ray analysis. The coordination mode of the phosphinoalkylnitriles in these complexes was found to be P-bonded resulting in a trans configuration. Palladium catalysts with 5a as ligand show high activies in the co-oligomerization of butadiene and carbon dioxide. The ^-lactone 11a is formed under very mild conditions.
	Reference	Z. Naturforsch. 51b, 934—946 (1996); eingegangen am 11. Juli 1995
	Published	1996
	Keywords	Phosphinoalkylnitriles, Phosphine Complexes of Palladium, Crystal Structure, Catalysis, -Lactones
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	TEI-XML for	default:Reihe_B/51/ZNB-1996-51b-0934.pdf
	Identifier	ZNB-1996-51b-0934
	Volume	51