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1.
Lithium salts of hydrazines react with fluorosilanes under formation of fluorosilylhydrazines and LiF. Five membered rings are obtained in the reaction of bis(fluorosilyl)-hydrazines with lithiated amines. The mass,1H-and19F-nmr spectra of the compounds are reported.
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2.
1-Phenylamino-2-imidazolines3 and 1,2,5,6-tetrahydro-1,2,4-triazines4, 5 and6 are synthesized from N-(2-chloralkyl)-imidchlorides1 and phenylhydrazines. As intermediates are obtained the hydrochlorides of amidrazones2 which cyclise. The structure of the different heterocyclic systems are determined by1H- and13C-NMR-spectroscopy.
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3.
The reaction of trimethylsilylcarbonamides with halogeno-diorganyl-boranes resp. trihalogenoboranes or organodihalogenoboranes gives monomeric resp. dimeric amidoboranes (borylcarbonamides) and derivatives of 4,8-diaza-1,5-dibora-2,6,9-trioxabicyclo[3.3.1]nonadienes. By reaction of the free acylamides with halogenoboranes in most cases the imide halides could be isolated as the only products. By reaction of the hydrochloride of bis(dimethylamino)-hydroxyborane withn-butyl-lithium followed by addition of the imide halides, the corresponding imidoylamines were formed.1H,11B, and19F-nmr spectra, mass spectra and characteristic ir group frequencies are reported.
15. Mitt.:W. Maringgele undA. Meller, Z. anorg. allg. Chem., im Druck.  相似文献   

4.
29Si-NMR spectras of some new cyclosilane derivatives were measured. First aspects of the dependence of chemical shift on ring size and kind of substituents are given.
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5.
A detailed study of early colour change in Scots pine (Pinus sylvestris) due to accelerated simulated sunlight exposure was undertaken focusing on the first 24 h of change. Colour changes were monitored with a Datacolor check spectrophotometer and compared with a set of controls. Measurements on both samples and controls were performed hourly for the first 24 h and there after daily until 168 h’ exposure with extra measurements at 200, 350 and 500 h. A subset of samples was extracted prior to exposure to check the effects of any colour change due to the presence of extractives. Data was analysed using the reflectance spectra (400–700 nm) as well as the CIE-L*a*b* system and ΔE. The majority of colour changes were found to occur within the first 24 h. This was unaffected by the removal of extractives from the wood and was independent of temperature. Mechanical properties and weight changes were also monitored to allow a comparison of sensitivity between the differing methods.  相似文献   

6.
The1H-NMR spin lattice relaxation times of aetiobiliverdin-IV- and biliverdindimethylester were determined using the inversion recovery technique. The relaxation times of protons attached to the terminal rings A and D are longer than those situated at the rings B and C which points to a higher mobility of rings A and D. Moreover these measurements allowed an independent assignment of the1H-NMR-signals of the methyl groups of biliverdindimethylester.
30. Mitt.:H. Falk undT. Schlederer, Ann. Chem., im Druck.  相似文献   

7.
The stoichiometry and structure of salicylidenebenzoic-hydrazine (SBH) chelates with UO2(II), Ce(III) and Th(IV) in buffer-ethanol mixtures and in pure ethanol is studied applying conductometric titration, visible spectrophotometry and ir-spectrophotometry. The ir-spectra revealed that coordination takes place through the C=O and C=N groups.Deceased December 1977.  相似文献   

8.
The interaction of 1-chlorodi-isophor-2(7)-en-3-one or its 5.11-bisnor-homologue with potassium phthalimide yields the corresponding 1-phthalimido-compounds, which are converted into the 1-amines on treatment with hydrazine, followed by hydrolysis. 1-Aminodi-isophor-2(7)-ene is not accessible by this route, but its N-acyl-derivatives are obtainable directly from 1-hydroxydi-isophor-2(7)-ene by theRitter reaction; the 3-keto-analogue reacts similarly. Some properties of the novel 1-aminodi-isophoranes are described.Die Einwirkung von Phthalimid-Kalium auf 1-Chlor-di-isophor-2(7)-en-3-on oder sein 5,11-Bis-nor-Homolog ergibt die entsprrechenden 1-Phthalimido-Ver Verbindungen, aus welchen durch Behandlung mit Hydrazin und darauffolgende Hydrolyse die primären 1-Amine erhältlich sind. 1-Amino-di-isophor-2(7)-en ist auf diese Weise nicht darstellbar, aber seine N-Acyl-derivate sind direkt aus 1-Hydroxy-di-isophor-2(7)-en mittels derRitter-Reaktion zugänglich; die analoge 3-Keto-verbindung reagiert ebenso. Einige Eigenschaften der neuen 1-Amino-di-isophorane werden beschrieben.Part 7:Kurzer, F., Morgan, A. R., Mh. Chem.112, 129 (1981).  相似文献   

9.
The synthesis of fifteen new (constitutionally nonsymmetrical) dithiaspirans having both sulfur atoms in the 7-membered ring is described. Some aspects of the conformation of the compounds are studied using1H nmr. Conformational transmission is observed in all cases.
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10.
The crystal and molecular structure of the polyunsaturated macrocyclic carbosilane 1,4,4,7,7,10,13, 13,16,16-decamethyl-1,4,7,10,13,16-hexasilabicyclo-[8.8.2]-eucosa-5,14-diene-2,8,11,17-tetrain containing SiC(sp), SiC(sp 2), and SiC(sp 3) endocyclic bonds was studied by XRD. The two strained 12-membered rings of this molecule have different (trans-zigzag and staggered) conformations. The lengths of the endocyclic bonds SiC(sp) are 1.821–1.852 Å, SiC(sp 2) 1.855–1.874 Å, and SiC(sp 3) 1.847–1.853 Å. The structure of the rings was solved by direct methods and refined by the full-matrix least-squares method. Calculations were carried out with SHELXTL PLUS 5.1 software.  相似文献   

11.
The application of combined1H- and13C-NMR-technics is used exemplarily for the elucidation of the type of substitution at the phenyl nucleus of indoles in 6,6-bis-indolylarylmethanes (1,2). These methods can be applied in general to analogous structure problems.
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12.
A precise, reliable, sensitive, and selective method for the determination of titanium(IV) is described. Titanium(IV) reacts withN 1-hydroxy-N 1,N 2-diphenylbenzamidine (HDPBA) and thiocyanate to form an orange-coloured mixed-ligand complex of stoichiometry 112 (Ti SCN HDPBA). The complex is quantitatively extractable into toluene from 0.05–0.15M hydrochloric acid. The spectrum of the complex exhibits an absorption maximum at 400 nm with a molar absorptivity of 20000M –1 cm–1 and the coloured system obeys Beer's law in the concentration range 0.20–3.0 gml–1 titanium. The effects of foreign ions and of various experimental parameters have been studied to establish the optimum conditions for the extraction and determination of titanium. The precision of the method has been evaluated and the relative standard deviation has been found to be 0.53%. The method has been successfully applied to the determination of titanium in synthetic matrices corresponding to titanium-containing ores, minerals, and alloys.  相似文献   

13.
Trimethylsilylacetamide and trimethylsilyltrifluoroacetamide react with halogenodiorganylboranes to monomeric or dimeric amidoboranes depending on the organyl substituents. The compounds were characterized analytically and spectroscopically (NMR:1H,19F,11B; MS; IR).
21. Mitt.:A. Meller, W. Maringgele, K. Hennemuth undU. Sicker, J. Z. anorg. allg. Chem., im Druck.  相似文献   

14.
Summary 1H,13C, and CP/MAS13C NMR spectra of sixp-substituted 1-aryl-3-arylamino-2-propen-1-ones in solution and in the solid state are reported and discussed. In the proteon-accepting solvent dimethylsulfoxide, electronegative substituents shift the isomeric equilibrium to the (E)-isomer. Bulky substituents promote crystallization of the (Z)-form.
NMR-Spektroskopische Untersuchung der (Z)/(E)-Isomerie von 1-Aryl-3-arylamino-2-propen-1-onen in Lösung und im Kristallzustand (Kurze Mitt.)
Zusammenfassung 1H-,13C- und CP/MAS-13C-NMR Spektren von sechsp-substituierten 1-Aryl-3-arylamino-2-propen-1-onen in gelöstem und festem Zustand werden berichtet und diskutiert. In protonenakzeptierendem Dimethylsulfoxid verschieben elektronegative Substituenten das Gleichgewicht zum (E)-Isomer. Große Substituenten begünstigen die Kristallisation in der (Z)-Form.
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15.
Seven ecdysteroids isolated from the aerial part of Silene linicola are identified using 1H and 13C NMR methods. Their yield from raw material was determined.  相似文献   

16.
The structure of galactomannans isolated from seeds of G. delavayi and G. aquatica was studied by 1H and 13C NMR spectroscopy. It was found that the galactomannans consisted mainly of β-1-4-bound mannopyranoses, a part of which was substituted on the C-6 hydroxyl by terminal units of α-galactopyranose.__________Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 12–13, January–February, 2005.  相似文献   

17.
L-Tyrosine-containing dipeptides valyl-tyrosine (H-Val-Tyr-OH) and tyrosyl-alanine (H-Tyr-Ala-OH) are characterized structurally by means of quantum chemical ab initio calculations and solid-state linear-dichroic infrared (IR-LD) spectroscopy. The IR-characteristic bands are assigned by application of reducing-difference procedure for polarized IR-spectra interpretation. Infrared data obtained are supported as well by the made vibrational analysis. The structures of both peptides are predicted on the basis of conformational analysis and structural information, obtained by the shown IR-spectroscopic tool.  相似文献   

18.
The formation of spin triplet, quintet, and singlet ground states within the 3d 6 electron configuration is investigated inD 4h , andD 3d symmetries employing irreducible tensor operator methods. Significant differences in the possible ground states are encountered between a complete CI and spin-orbit interaction treatment and an approximate calculation within the cubic5 T 2,1A1,3 T 1, and3 T 2 parents.  相似文献   

19.
The effect ofN-oxidation of a series of polychloropyridines on13C NMR parameters has been studied. It has been established that inN-oxides of polychloropyridines an electric field through-space effect of theN-oxide group predominates in the shielding of the -carbon atom compared to the other carbon atoms. A linear correlation between13C NMR chemical shifts and total charge densities calculated by the MNDO method for the carbon atoms ofN-oxides of polychloropyridines has been found.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2425–2428, December, 1995.The authors are grateful to V. V. Kolchanov for help in the synthesis of compounds under study.  相似文献   

20.
Starting from (+) (2R) methyl 5-ethyl-2,2-spirobiindane-5-carboxylate of known enantiomeric purity 79 optically active, configurationally correlated 5,5,6-trisubstituted 2,2-spirobiindanes (2–7) were prepared for the purpose of testing a shortened polynomal Ansatz for chirality functions. Their optical rotations and1H-nmr spectra are reported.In this context several 6-substituted 5-ethylindanes (1) were prepared as model compounds for synthetic transformations.
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