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1.
Summary Dichloro complexes of PdII, [Pd(L–L)Cl2], where L–L=1-(thiomethyl)-2-(diphenylarsino)ethane (S–As) or 1-(thiomethyl)-2-(diphenylphosphino)ethane (S–P) andtrans-[PdL2Cl2], where L=diphenyl(2-phenylethyl)-phosphine (PE), diphenyl(1-naphthyl)phosphine (PN) orN-methyl-2-thiophenealdimine (SN), have been prepared and characterized. The reactions of these complexes with MeLi were investigated. The dimethyl complexes [Pd(L–L)Me2] (L–L=S–As, S–P) and [Pd(PE)Me2] were isolated and characterized. Reaction of [Pd(L–L)Me2] (L–L=S–As, S–P) with HCl affords the monomethyl derivatives [Pd(L–L)Me(Cl)]. In contrast to the Pt analogues, [Pd(L–L)Me2] and [Pd(L–L)Me(Cl)] are relatively less stable than [Pt(L–L)Me2] and [Pt(L–L)Me(Cl)].  相似文献   

2.
Summary. The reaction of [RuCp(CH3CN)3]PF6 with 1 equiv of N-Me-imidazole results in the quantitative formation of [RuCp(1N-N-Me-imidazole)(CH3CN)2]PF6 (1) featuring a 1N rather than a 1C bound N-Me-imidazole ligand. According to DFT/B3LYP calculations, 1N coordination of N-Me-imidazole is preferred over 1C coordination by 25.5kJ/mol. Upon exposure to air 1 reacts with oxygen and water to afford the novel hydroxo-bridged dinuclear complex of [Ru2Cp2(1N-N-Me-imidazole)2(-OH)2](PF6)2 (2) featuring a metal-metal single bond. The dimeric nature of 2 was confirmed by a single-crystal X-ray structure analysis.  相似文献   

3.
A convenient method has been developed for the synthesis of 5-methyl-2-desoxyuridines. Chlorination of 5-O-benzoyl-5-methyluridines with a mixture of Ph3P and CCl4 in DMF affords the 2-desoxy-2-chloro-derivatives, which are then reduced with tributyltin hydride. The crystalline 5-O-benzoyl-5-methyl-2-desoxyuridines were obtained in overall yields of 40–60%. In a similar way, 5-O-benzoyluridine has given 5-O-benzoyl-2-desoxyuridine.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 246–248, February, 1989.  相似文献   

4.
The passage of dry gaseous hydrogen chloride through chloroform solutions or acetone suspensions of S-substituted N1,N4-di(salicylidene)isothiosemicarbazidates of nickel (Ni(LRR)) has led to a demetallization reaction with the liberation in the free state of S-substituted N1,N4-di(salicylidene)isothiosemicarbazides with the general formula N2LRR (where R is H and R is CH3 (I); R is H and R is C2H5 (II); R is H and R is C3H7 (III); R is H and R is C7H7 (IV); and R is CH3 and R is CH3 (V)). The IR spectra of (I-IV) each showed bands characteristic for an aromatic ring and groups in the 1600–1500 cm–1 region, with a band of the deformation vibrations of an OH group at 1300 cm–1. The PMR spectra in CDCl3 each had two singlets at 12.15-11.25 and 9.00-8.36 ppm which were assigned, respectively, to the protons of an OH group and those of a =CH group. A multiplet in the 7.70-6.83 ppm region belonged to the protons of benzene rings. In the region of lower fields there were the signals of the substituents R and R. In the mass spectra of (I-V), the peaks of the molecular ions, and also the characteristic fragments OH, R, SR, and HSR have been detected.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 21, No. 5, pp. 604–608, September–October, 1985.  相似文献   

5.
Conclusions We synthesized two analogs of the natural coenzyme adenosine diphosphate glucose: N6-methyl-ADPG and N6, N6-dimethyl-ADPG.For communication 11, see [1].The following abbreviations are used in this article: ADPG) adenosine-5'-diphosphate-a-D-glucopyranose; N6-methyl-ADPG) N6-methylamino-9--D-ribofuranosylpurine-5-diphosphate--D-glucopyranose; N6, N6-dimethyl-ADPG) N6, Ng-dimethylamino-9--D-ribofuranosylpurine-5-diphosphate--D-glucopyranose.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2514–2521, November, 1969.  相似文献   

6.
    
A universal key component is proposed for the preparation of oligonucleotides with 3- and 5-terminal phosphate groups — 2,3-dibenzoyluridin-5-yl (4-chlorophenylphosphate) (pU(Bz)2), which is a potential source of the phosphate group. The condensation ofpU(Bz)2 with the 5-OH or the 3-OH group of a protected oligonucleotide leads to the formation of oligodeoxyribonucleotides with 5- or 3-terminal uridine, respectively. The oxidation of the 2,3-cis-glycol group of the terminal uridine unit followed by -elimination forms oligodeoxyribonucleotides with terminal phosphate groups.M. V. Lomonosov Moscow State University. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 731–734, September–October, 1987.  相似文献   

7.
The partial molar heat capacities, C o p,2, and partial molar volumes, V o 2, at infinite dilution have been determined for the compounds N-acetyl-N-methylglycinamide, N-acetyl-N-methylalaninamide, N-acetyl-N-methylvalinamide, and N-acetyl-N-methylleucinamide in aqueous solution at the temperatures 15, 25, 40, and 55°C. The C o p,2 and V o 2 results have been used to calculate amino acid side-chain contributions to the thermodynamic properties. These side-chain contributions are compared with those derived in previous work using thermodynamic data for the corresponding acetylated primary amides and with results reported using peptide model compounds.  相似文献   

8.
Summary Cobalt(II) and nickel(II) halide complexes of the ligands 2-(2-methyl-8-quinolyl)benzoxazole (mqbo), 2-(2-methyl8quinolyl)benzimidazole (mqbi) and 2-(4-methyl-8-quinolyl)benzimidazole (mqbi) were synthesized and characterized by analytical, thermogravimetric, conductivity and magnetic data, and i.r. and electronic spectra.The ligands are bidentate N-donors yielding complexes where the coordination geometry depends on the metal ion and steric hindrance. All the cobalt complexes have formula [CoL2X2] and distorted tetrahedral geometry. Different types of nickel compounds were obtained: i) complexes of formula NiLX2 · n H2O (or EtOH) (L = mqbo or mqbi; n=0–1.5) which arepseudo-tetrahedral or five-coordinate and ii) complexes NiL2X2 · n H2O (L = mqbi, n=3 or 4) where the metal is bound to four nitrogen atoms and the overall coordination geometry is tetragonal. The structural changes occurring after removal of water or alcohol from the complexes are also reported.  相似文献   

9.
-Diimines, RN:C(R)C(R):NR(LL) derived from glyoxal, GLL (R=H) abbreviated as GAA (R= R=4-dimethylaminophenyl) or GHA (R= R=4-hydroxyphenyl), and derived from biacetyl, BLL (R=Me) abbreviated as BDH (R=R= NH2), BOH (R=NH2, R=OH) react with carbonylrhodium(I) compounds to give different products depending on the imino substituents in the ligand and/or the solvent employed. The reaction of -diimines bearing amino groups, such as GAA or BDH with [RhCl(CO)2]2 in acetone yields binuclear [RhCl(CO)2]2(-LL) while in CH2Cl2 ionic [Rh- (CO)2(LL)]+[RhCl2(CO)2] species are obtained. In acetone [RhCl(CO)2]2(-GAA) exists as an equilibrium mixture between two different neutral binuclear species; [Rh(CO)2(BDH)]+ exists as a mixture of two species containing chelate or monodentate bonded diimine respectively. GAA or BDH react in situ with [RhCl(CO)(C2H4)]2 in benzene to yield tetracoordinated monocarbonylated [RhCl(CO)(LL)] compounds. -Diimines (LL) bearing hydroxy groups, such as GHA or BOH react with [RhCl(CO)2]2 or [RhCl(CO)(C2H4)]2 to give pentacoordinated dicarbonylated [RhCl(CO)2(LL)] compounds.  相似文献   

10.
Summary 4-(1H-1,2,4-Triazolyl-3-azo)-2-methylresorcinol reacts with vanadium(V) at pH 8.10 (Tris-HClO4 buffer solution) to produce a pink-violet 11 complex ( max=525 nm,=2.55×104l·mol–1· cm–1) in a 50% (v/v) methanol-water medium, which allows the spectrophotometric determination of 0.1 to 1.51 ppm of vanadium. The method has been applied for the determination of the vanadium content in low alloy steels.
Spectrophotometriscbe Bestimmung von Vanadin mit 4-(1H-1,2,4-triazo-lyl-3-azo)-2-methylresorcin
Zusammenfassung Vanadin bildet bei pH 8,10 (Tris-HClO4-buffer) mit 4-(1H-1,2,4-tri-azolyl-3-azo)-2-methylresorcin ein rosenrot-violettes Chelat, dessen Absorptionsmaximum bei 525 nm in Gegenwart von 50% Methylalkohol gemessen wird. Dieser 11-Komplex entspricht bei einer Vanadin-Konzentration von 0,1–1,51g/ml dem Beerschen Gesetz; seine molare Absorptivität ist 2,55×104l·mol–1·cm–1. Das Verfahren wurde zur Bestimmung des Vanadins in Stahl verwendet.
  相似文献   

11.
Summary Rhodium(I) and iridium(I) mixed complexes of the formulae [M(diolefin)LL]ClO4, [M(diolefin)L2L]ClO4, [(diolefin)LIr(-L)2IrL(diolefin)](ClO4)2, [(diolefin)LM(-L-L)ML'(diolefin)](ClO4)2, [(diolefin)Rh{-(L-L)}2Rh(PPh3)2](ClO4)2 and [(diolefin)LIr{-(L-L)}2IrL (diolefin)](C1O4)2, (L=monodentate sulphur ligand, L-L=bidentate sulphur ligand, L=group Vb ligand; M=Rh, diolefin=1,5-cyclooctadiene (COD) or 2,5-norbornadiene (NBD); M=Ir, diolefin=COD) are described.Author to whom all correspondence should be directed.  相似文献   

12.
A new method of determination of HCCH isomers by thermogravimetry is described. The thermal changes of the isomers, the decomposition characteristics and the parameters for identification are discussed.
Zusammenfassung Eine neue Methode der Bestimmung von HCCH-Isomeren durch Thermogravimetrie wird beschrieben. Die thermischen Änderungen der Isomere, die Zersetzungscharakteristika und die Identifizierungsparameter werden erörtert.

Résumé On décrit une nouvelle méthode de détermination des isomères HCCH par thermogravimétrie. On discute les modifications thermiques des isomères, les caractéristiques de décomposition et les paramètres d'identification.

. , .


We are grateful to Dr. B. L. Amla, Director of this Institute, for his encoragement, and to Shri Hanumantha Rao Judav for his assistance.  相似文献   

13.
Starting from optically active 5,5-dimethyl, diethyl, and 5-ethyl-5-methyl-2,2-spirobiindane as well as from 5-ethyl-spirobiindane-5-carboxylic ester of known enantiomeric purity and configuration 75 mono to polysubstituted 2,2-spirobiindanes have been prepared. Amongst these are several compounds with rings anellated in the 6,7 (and 6, 7) positions, especially a spirohydrocarbon4 x with orthogonal naphthalene units the circular dichroism of which is reported and discussed.Several mono and disubstituted 5-methyl and ethylindanes (1,2) have been prepared as models for synthetic transformations in the spirobiindane series.From the molar rotations of symmetrically diacylated 5,5-dimethyl and diethyl spirobiindanes (4a, 7b, 7c) empirical ligand parameters for acetyl and methoxycarbonyl were determined which gave much better results in the calculation of the rotations of appropriate spirobiindanes (with the shortened polynomal Ansatz) than the -values deduced previously from 5,5-disubstituted spirobiindanes. The significance of these results is briefly discussed.
10. Mitt.:Neudeck, H., Schlögl, K., Angew. Chem.92, 318 (1980), Intern. Ed. Engl.19, 308 (1980).  相似文献   

14.
The pK-values of the first and second degree of dissociation of 2.2-dihydroxy-5-methyl-3.5-dinitro-diphenylmethane, 2.2-dihydroxy-5-methyl-5-nitro-diphenylmethane and 2.2-dihydroxy-5.5-dimethyl-3-nitro-diphenylmethane were determined in aqueous solution at 25°C spectrophotometrically. Comparing the observed pK-values with those of 2-methyl-4.6-dinitrophenol, 2-methyl-4-nitrophenol, 2.4-dimethyl-6-nitro-phenol and 2.4-dimethylphenol, we found a decrease of the values of pK 1 and an increase of pK 2. We explain this by the formation of an intramolecular hydrogen bridge which stabilizes the anion of the half dissociated form. This assumption is supported by the UV spectra.

Mit 3 Abbildungen  相似文献   

15.
Zusammenfassung Es wird die quantitative Bestimmung der 5 Amine rac-N,N-Dibutyl-,-diphenyläthylendiamin (A), meso-N,N-Dibutyl-,-diphenyläthylendiamin (B), 1-Phenyl-1-butylamino-2-methyl-propan (C), N-Butyl-benzylamin (D) und Butylamin (E) in Reaktionsgemischen durch 54- und 95 stufige Craig-Nach-fraktionierungsprozesse in einer Verteilungsbatterie mit 35 Elementen nach Hecker [1] beschrieben. Durch graphische Auswertung der überlappenden Verteilungskurven wird eine quantitative Bestimmung auch bei 54 stufigen Prozessen, d.h. bei unvollständiger Trennung möglich.
Quantitative determination of amine mixtures by multiplicative distributionOn the separation of organic bases by Craig distribution. IX
The quantitative evaluation of the 5 amines, rac-N,N-dibutyl-,-diphenylethylenediamine (A), meso-N,N-dibutyl-,-diphenylethylenediamine (B), 1-phenyl-1-butylamino-2-methyl-propane (C), N-butyl-benzylamine (D) and butylamine (E) in reaction mixtures by Craig after-fractionation processes of 54 and 95 steps in a distribution machine with 35 elements by Hecker [1] is described. By graphic evaluation of the overlapping distribution curves a quantitative determination is achieved, even with processes of 54 steps, i. e. incomplete separation.


8.Mitteilung: Sohönenberger, H., Eder, M.: diese Z. 249, 117–120 (1970).

Wir danken der Deutschen Forschungsgemeinschaft und dem Fonds der Chemischen Industrie für die Förderung unserer Untersuchungen.  相似文献   

16.
Summary. ESR and ENDOR spectra are reported of several symmetrical substituted N,N,N,N-tetraalkyl-p-phenylenediamine radical cations in solution. Different N,N-alkyl substituted para-phenylenediamines, like the ethyl, n-propyl, and iso-propyl derivative are compared with the parent N,N,N,N-tetramethyl-p-phenylenediamine (Wursters Blue Cation). N,N,N,N-Tetrabenzyl-p-phenylenediamine, 1,4-dipyrrolidinylbenzene, and N,N-bis[4-(dimethylamino)phenyl]piperazine are additionally investigated. Experimental and calculated hyperfine coupling constants are compared. Characteristic UV-VIS data and redox potentials in acetonitrile are reported, together with the syntheses of the compounds.  相似文献   

17.
Cyclization of 2-methyl (or -phenyl)-5-phenylthiazole-4-carbohydrazides (1) and (2) under various conditions gives differing oxadiazoles: 2-(2-substituted-5-phenyl-4-thiazolyl)-1,3,4-oxadiazole-5-thiones (7) and (8), and 2-(2-substituted-5-phenyl-4-thiazolyl)-1,3,4-oxadiazoles (9) and (10). Cyclodehydration of thiazolecarbonyl-thiosemicarbazides (3)–(6) with NaOH givesthe 3-(2-substituted-5-phenyl-4-thiazolyl)-4-substituted-4H-5-mercapto-1,2,4-triazoles (11)–(14), while H 3 PO 4 gives the 2-(2-substituted-5-phenyl-4-thiazolyl)-5-phenylamino-1,3,4-thiadiazoles (15) and (16).A. E. Arbuzov Institute of Organic and Physical Chemistry, Kazan Science Center, Russian Academy of Sciences, 420083 Kazan'. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 3, pp. 679–683, March, 1992.  相似文献   

18.
Conclusions A new coumarin, C24H26O7, which has been called andelin, has been isolated from the roots of the white-flowered form ofAngelica decursiva Franch. et Savat.On the basis of its IR, UV, and NMR spectra and the characteristics of a number of derivatives, the structure of 4-angel oyloxy-3-senocioyloxy-3,4-dihydxopyrono-5,6:6,7-coumarin has been proposed for andelin.  相似文献   

19.
Condensation of phenothiazine with phenyl isocyanide dichloride has given 10(N-phenylchloroformimidoyl)phenothiazine, exchange reactions of which with salts of diakylthio- and dithiophosphoric acids result in rearrangement of the initially formed 10-[N-phenyldialkoxy(thio)phosphorylthioformimidoyl]phenothiazines to 10-{N-phenyl-N-[dialkoxy(thio)phosphoryl]thiocarbamoyl}phenothiazines, while reaction with diisopropyl dithiophosphoric acid affords diisopropyl chlorothiophosphate, phenyl isothiocyanate, and phenothiazine. 10-(N-Phenylethoxyformimidoyl)phenothiazine alkylates dithiophosphoric acid to give 10-(N-phenylcarbamoyl)phenothiazine, while N2-phenyl-N1,N1-diethyl-(10-phenothiazinyl)formamidine reacts with diisopropyl dithiophosphoric acid, affording the salt N2-phenyl-N1,N1-diethyl-(10-phenothiazinyl)formamidinium O,O-diisopropyl dithiophosphate.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2596–2601, November, 1989.  相似文献   

20.
The degradation of a rocket insulator compound based on ethylene propylene diene rubber (EPDM) containing asbestor, cork and iron oxide (Fe2O3) as fillers has been studied at high temperature (up to 600°) by using differential thermal analysis (DTA) and thermogravimetry (TG). The changes in physical properties on high-temperature aging are also reported. EPDM gum vulcanizates involving different types of diene, namely ethylidene norbornene (ENB), dicyclopentadiene (DCPD) and 1,4-hexadiene (HD), were used. In each case, the kinetic parameters for degradation have been evaluated. From these data, the lifetime of the rocket insulator compound has been found.
Zusammenfassung Die Zersetzung einer Raketenisolator-Verbindung auf Äthylen-Propylen-Dien-Gummibasis (EPDM) mit Asbest, Kork und Eisenoxid (Fe2O3) als Füllstoffe wurden bei hohen Temperaturen (bis 600°) mittels Differentialthermalanalyse (DTA) und Thermogravimetrie (TG) untersucht. Die bei Hochtemperaturen eintretenden Veränderungen der physikalischen Eigenschaften sind ebenfalls angegeben. Verschiedene Typen von Dienen, nämlich Äthyliden-norbornen (ENB), Dicyclopentadien (DCPD) und 1,4-Hexadien (HD) enthaltenden EPDM-Gummivulkanisate waren Gegenstand der Untersuchung. In allen Fällen wurden die kinetischen Parameter der Zersetzung ermittelt. Aus diesen Daten wurde die Lebensdauer der Raketenisolator-Verbindung bestimmt.

600° (), , . , . , , 1,4- . . .


The authors are grateful to the Indian Space Research Organization for funding, and acknowledge the help and suggestions from Mr. T. S. Ram and Mr. Baby John, R.P.P., V.S.S.C., Trivandrum. The authors are also grateful to Prof. S. K. De, Rubber Technology Centre, and Prof. R. Ghosh, Chemistry Department, I.I.T., Kharagpur.

The authors thank Mr. Asutosh Ghosh, Indian Association for the Cultivation of Science, for experimental assistance.  相似文献   

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