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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.
Ni(II) and Co(II) complexes with deprotonated paramagnetic enaminoketones 4(3,3,3trifluorine2oxopropylidene) 2,2,5,5tetramethyl3imidazolidine1oxyl (L) and 4(3,3,3trifluorine1chlorine2oxopropylidene)2,2,5,5tetramethyl3imidazolidine1oxyl (L1) and alcohols are shown to form continuous solid solutions NixCo1-xL2(C2H5OH)2 and NixCo1-xL2 1(CH3OH)2. Single crystal Xray diffraction analysis showed that concentration variation practically does not affect the structural characteristics of the solid solutions. Distinguishing features if the magnetic behavior of NixCo1-xL2 · (C2H5OH)2 and NixCo1-xL2 1(CH3OH)2 are the antiferromagnetic interaction of the moments of the nickel and cobalt sublattices inside the polymeric layers and the antiferromagnetic nature of interlayer interaction of the magnetic moments.  相似文献   

3.
Conclusions The reaction of 1,2-bis(methyldimethoxysilyl)ethane and the corresponding ethylene and acetylene derivatives with bis(2-hydroxyethyl)methylamine gives 1,2-bis(2,6-dimethyl-1,3-dioxa-6-aza-2-silacyclooctyl-2)ethane and the corresponding ethylene and acetylene derivatives. Analogously, 1,2-bis(vinyldimethoxysilyl)acetylene gave 1,2-bis(2-vinyl-6-methyl-1,3-dioxa-6-aza-2-silacyclooctyl-2)acetylene.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 6, pp. 1420–1421, June, 1988.  相似文献   

4.
Summary During interaction of ethanol-triethyl orthoformate solutions of nicotinic or isonicotinic acidN-oxides (LH and LH, respectively) with MCl2 (M = Mn, Co, Ni), only one true adduct, of the Ni(LH)3Cl2 · 2 H2O type was obtained. In all other cases, partial substitution of Cl ions with the corresponding pyridinecarboxylateN-oxide anionic ligands (L or L) occurred. As a result, mixed ligands (LH-L or LH-L) were precipitated, as follows: Mn(LH)2LCl, Co(LH)LCl, Mn(LH)LCl · 4H2O, Co(LH)LCl · H2O and Ni2(LH)LCl3 · 6 H2O. The insolubility of the new complexes in all common solvents, combined with the pronounced tendency of the 3- and 4-pyridinecarboxylates and theirN-oxides to function as bidentate bridging ligands, favours bi- or polynuclear structures. Spectral data suggest that Ni(LH)3Cl2 · 2 H2O is hexacoordinate, and the rest of the new complexes pentacoordinate. Bi- or polynuclear structures, involving double -M-(L)2-M- or-M-(LH)2-M- and single -M-(L)-M- or-M(L)-M-(LH)-M- bridges, were proposed on the basis of the overall evidence; additional features of the proposed structural types are: exclusively coordinated chloro ligands, in all cases; aqua ligands [Co(LH)LCl · H2O]; lattice water [Ni(LH)2Cl2 · 2H2O]; both lattice and coordinated H2O [Mn(LH)LCl · 4H2O, and Ni2(LH)LCl3 · 6H2O]; and, with the exception of Ni2(LH)LCl3 · 6 H2O, terminal, unidentate, N-O oxygen-bonded LH or LH ligands.Abstracted in part from the Ph.D. Thesis (in preparation) of L. S. Gelfand, Drexel University.  相似文献   

5.
Summary Vanadium(III) chloride reacts with 1,10-phenanthroline and 2,2-bipyridyl, and with substituted derivatives of each ligand (B), in ethanol or in acetonitrile as solvent (L), to yield two different series of complexes. These are (a) the neutral species VCl3BL, where B = 1,10-phenanthroline, 5-chloro-1,10-phenanthroline, 5-methyl-1,10-phenanthroline, 4,7-dimethyl-1,10-phenanthroline, 2,2-bipyridyl, 4,4-dimethyl-2,2-bipyridyl, L = ethanol. The complexes in which B = 1,10-phenanthroline or 2,2-bipyridyl were also obtained with L = acetonitrile, (b) [VCl2B2]+[VCl4B] where B is the same series of ligands listed above. Vanadium(III) chloride yields VCl3 (terpy) with 2,2,2 -terpyridyl. All the complexes have been characterised by elemental analyses, conductance measurements, electronic- and i.r. spectral measurements, and by their temperature-range (297–77 K) magnetic moments; ring substituents have little influence on any chemical or physical properties of these complexes.  相似文献   

6.
Summary In an attempt to develop potential inhibitors ofUDP-glucuronosyltransferase, some 5-O-amino acid derivatives of uridine were synthesized. N-protectedL-amino acids were coupled at the 5-O-position of 2,3-O-isopropylideneuridine by esterification employing the method of symmetrical anhydrides in presence of 4-dimethylaminopyridine, 5-O-(N-benzyloxycarbonyl-O-tert.butyl-L-threonl)-23-O-isopropylideneuridine (1), 5-O-(N-tert.butyloxycarbonyl-O-benzyl-L-seryl)-2,3-O-isopropylideneuridine and (2), 5-O-(N-tert.butyloxycarbonyl-L-valyl)-2,3-O-isopropylideneuridine (3), and 5-O-(N-tert.butyloxycarbonyl-L-valyl)-2,3-O-isopropylideneuridine (4) were obtained in good yield after column chromatography on silica gel. The treatment of2 withTFA/CH2Cl2 (6:1) at room temperature for 30 min led to a selective removal of theBoc group without deblocking of the 2,3-O-isopropylidene group of uridine. Treatment of2 withTFA/H2O (5:1) at room temperature for 1 h, however, released bothBoc and 2,3-isopropylidene groups. TheZ group of1 was deprotected by catalytic hydrogenolysis over 10% Pd/C/ammonium formate.
Synthese von 5-O-Aminosäurederivaten des Uridins als potentielle Inhibitoren derUDP-Glukuronosyl-Transferase
Zusammenfassung In einem Versuch, potentielle Inhibitoren derUDP-Glukuronosyl-Transferase zu entwickeln, wurden einige 5-O-Aminosäurederivate des Uridins synthetisiert. N-GeschützteL-Aminosäuren wurden durch Veresterung mit der 5-O-Position des 2,3-isopropylidenuridins gekuppelt (Methode der symmetrischen Anhydride in der Gegenwart von 5-Dimethylaminopyridin). Solcherweise wurden 5-O-(N-Benzyloxycarbonyl-O-tert.butyl-L-threonly)-2,3-O-isopropylidenuridin (1), 5-O-(N-tert.Butyloxycarbonyl-O-benzyl-L-seryl)-2,3-O-isopropylidenuridin (2), 5-O-(N-tert.Butyloxycarbonyl-L-leucyl)-2,3-O-isopropylidenuridin (3) und 5-O-(N-tert.Butyloxycarbonyl-L-valyl)-2,3-O-isopropylidenuridine (4) nach Säulenchromatographie (Kieselgel) in guter Ausbeute hergestellt. Die Behandlung von2 mitTFA/CH2Cl2 (6:1) bei Zimmertemperatur (30 min) führte zu einer selektiven Abspaltung derBoc-Gruppe ohne Deblockierung der 2,3-O-Isopropylidengruppe des Uridins. Eine Behandlung von2 mitTFA/H2O (5:1) bei Zimmertemperatur für 1 Stunde führte hingegen zur Abspaltung sowohl derBoc als auch der 2,3-O-Isopropylidengruppe. DieZ-Gruppe von1 wurde durch katalytische Hydrogenolyse auf 10% Pd/C/Ammoniumformiat abgespalten.
  相似文献   

7.
Summary Several new N-acyl derivatives of 1-(4-hydroxy-2,3-dihydrobenzofuran-5-yl)-7,8-di methoxy-1,9 b,2,3,3 a,4-hexahydro-[1]benzopyrano[3,4-c]pyrazole-1-ene have been prepared by appropriate chemical transformation of isohydrazones of rotenone and amorphigenin. A study of their1H- and13C-NMR spectra confirmed the presence of the twocis 3a, 9b, 2 and 3a, 9b, 2 diastereomers in the parent isohydrazones and revealed the strong predominance of the conformers withendo orientation of the 3-NAc group. The conformations due to rotation about the 1,5-bond between rings C and D in the 4-OH and 4-O-substituted compounds were also determined by taking into account the anisotropic effect of aromatic rings A and D, and the hydrogen bond between 4-OH and the 2-N atom, as well as by inspecting the Dreiding models.
Darstellung und stereochemische Charakterisierung einiger N-Acyl-[1]benzopyrano[3,4-c]pyrazol-Derivate von Rotenoiden
Zusammenfassung Mittels geeigneter chemischer Transformationen von Isohydrazonen von Rotenon und Amorphigenin wurden einige neue N-Acyl-Derivate von 1-(4-Hydroxy-2,3-dihydrobenzofuran-5-yl)-7,8-dimethoxy-1,9 b,2,3,3 a,4-hexahydro-[1]benzopyrano[3,4-c]pyrazol-1-en hergestellt. Eine Untersuchung ihrer1H und13C-NMR-Spektren zeigt die Gegenwart von zweicis 3a, 9b, 2- und 3a, 9b, 2-Diastereomeren in den Ausgangs-Isohydrazonen und eine starke Bevorzugung der Konformeren mitendo-Orientierung der 3-NAc-Gruppe. Die Konformationen bezüglich der Rotation um die 1,5-Bindung zwischen Ring C und D werden für die 4-OH und 4-O-substituierten Verbindungen unter Berücksichtigung von Anisotropie-Effekten der aromatischen A- und D-Ringe, der Wasserstoffbrücken zwischen 4-OH und dem 2-N Atom und auch der Betrachtung der entspechenden Dreiding-Modelle diskutiert.
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8.
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   

9.
Conclusions 1. Xanthalin has been shown to have the structure of 2, 2-dimethyl-3, 4,-diangeloyloxy-3, 4-dihydropyrano-5, 6:6, 7-coumarin on the basis of the preparation of a number of derivatives and cleavage products.2. The following products of the alkaline hydrolysis of xanthalin have been isolated and characterized for the first time: (±)-3, 4-dihydroxy-3, 4-dihydroxanthyletin (isokhellactone), C14H14O5, with mp 213–215° C and (–)-trans-3-hydroxy-4-methoxy-3, 4-dihydroxanthyletin (isomethylkhellactone, C15H16O5, with mp 136.5–138° C and [] D 20 –47.7 (ethanol).Khimiya Prirodnykh Soedinenii, Vol. 6, No. 1, pp. 14–19, 1970  相似文献   

10.
The two major fundamental obstacles which so far have prevented theisolation of stable silynes, RSiCR (1), are: (a)the existence of more stable isomers, e.g., RRC=Si: (2) and(b) their extremely facile (exothermic) dimerication. The steric andelectronic effects of various substituents R and R (R = alkoxy,alkyl, aryl and silyl; R = alkyl and aryl groups) on the stability ofRSiCR relative to the isomeric RRC=Si:(E(1-2)), and on the energy of dimerization tothe corresponding 1,3-disilacyclobutadienes (E(D)), werestudied computationally using density functional theory (DFT) and theONIOM method. The goal was to find a combination of substituents thatwill make RSiCR more stable than RRC=Si: and whichwill also prevent its dimerization. For R = R = H,E(1-2)) = 40.7 kcal/mol (i.e., 2 islower in energy than 1), and E(D) = –104.0kcal/mol. 1, R = OH, R = m-Tbt 2,6-bis[bis(silyl)methyl]phenyl, is by 11.1 kcal/mol morestable than the isomeric silylidene 2. However, thedimerization of 1, R = OH, R = m-Tbt remains highlyexothermic (by 101 kcal/mol). 1, R = R = m-Tbt and1, R = (t-Bu)3Si, R = m-Tbt, are by 5.8 and 2.0kcal/mol, respectively, less stable than the corresponding 2.However, the dimerization of 1, R = (t-Bu)3Si, = m-Tbt is exothermic by only 12 kcal/mol. For1, R = (t-Bu)3Si, and R = Tbt 2,6-bis[bis(trimethylsilyl)methyl]phenyl, the corresponding1,3-disilacyclobutadiene dimer 3, dissociates spontaneously.Thus, (t-Bu3Si)SiCTbt is predicted to be kineticallystable towards both, isomerization to (t-Bu3Si)TbtC=Si: anddimerization to 3, making it a viable synthetic target. Thereported energies were calculated atB3LYP/6-31G**//B3LYP/3-21G*; good agreement is found betweenthe DFT and the ONIOM results.  相似文献   

11.
Reduction of 1-alkyl-3-(2-quinolyl)quinolinium halides with sodium borohydride leads to 1-alkyl-1,2-dihydro-2,3-biquinolyls which, except for the ethoxycarbonyl derivative, undergo rearrangement to 1-alkyl-1,4-dihydro-2,3-biquinolyls. The last can be synthesized by the alkylation of the corresponding 1,4-dihydro-2,3-biquinolyls under conditions of interphase catalysis and in the system KOH-DMSO.For Communication 7, see [1].Stavropol' State University, Stavropol' 355009, Russia; nauka@stavsu.ru. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1084–1087, August, 2000.  相似文献   

12.
Reaction of N-(1-pyrrolidinyl)-, N-(1-piperidinyl)-, N-(4-morpholinyl)-, and N-(1-hexahydroazepinyl)-thioureas with propiolic acid gives hetero-N-spiro-4-(2-amino-2-1,3,4-thiadizolin-4-io-5-acetates), which rearrange in acetic anhydride to 2-(N-heteryl)imino-2,3-dihydro-4H-1,3-thiazin-4-ones.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 263–265, February, 1993.  相似文献   

13.
Mixed-ligand vanadyl(IV) and vanadyl(V) complexes with tridentate ONO donor azophenolalcoholate/aldiminealcoholates [viz., 2-hydroxy-2-hydroxymethyl-5-methylazobenzene (H2L1), N-(2-hydroxymethylphenyl)-salicylaldimine (H2L2) and N-(2-hydroxymethylphenyl)1-hydroxy-2-naphthaldimine (H2L3)] and bidentate NN [viz., 2,2-bipyridine (bipy) and 1,10-phenanthroline (phen)] or NO [viz., 8-hydroxyquinoline (Hhq)] donor ligands have been prepared and characterized by elemental analyses and by i.r., e.p.r. and u.v.–vis. spectroscopies. The data show that the vanadyl(IV) complexes exist in two isomeric solid forms viz., monomers and polymers, whereas vanadyl(V) complexes exist only in the monomeric form. The polymeric structure results from intermolecular V=OV=O interactions. The complexes with NN donor ligands are one electron paramagnetic and display two ligand-field transitions in the visible region, whereas the complexes with ON donor ligands are diamagnetic and exhibit only LMCT bands. The vanadyl(IV) complexes display an irreversible oxidation peak near +0.30 V for complexes with (L1)2– and near +0.55 V for complexes with (L2)2– and (L3)2– ligands, while the vanadyl(V) complexes display a quasi-reversible one electron reduction couple near –0.23 V versus s.c.e. The trends in the (V=O), values for the visible region transitions and the redox potential values for the vanadyl(IV) complexes have been scrutinized.  相似文献   

14.
Summary New chiral cyclopentadienyl-titanium and-zirconium complexes Cp2TiCl2, CpCpTiCl2 and Cp2ZrCl2 (Cp=5 -cyclopentadienyl and Cp=substituted cyclopentadienyl), have been synthesized. The (S,S)-3 complex, which forms red plate crystals, has been studied by x-ray analysis. It belongs to the monoclinic space groupC2, witha 23.963(3),b 6.6470(6),c 12.6618(9) Å, 103.089(7)°, V=1964.4(3) Å3 and Z=4. The structure was relined to an R factor of 0.048 for 868 observed reflections.  相似文献   

15.
Summary The conditional protonation constants (=0.1) for 2,2:6,2-terpyridine, logK 1=4.93, logK 2=3.69, were determined by thepH-metric method. The compositions of complexes of Ag2+ and Ag+ ions with 2,2:6,2-terpyridine (tp) were studied and equilibria of the complex formation process were described. The values of conditional complex formation constants are as follows: for Ag(tp) 2 + :log01=5.79, log02=9.68, for Ag(tp) 2 2+ :log02=25.31, while the conditional constant of the Ag(tp)NO3 precipitate formation is:K SO=2.45·104. Using coulometric and chronovoltamperometric measurements, the redox systems being formed in the complex solutions of Ag(II) and Ag(I) were determined and described including their formal potentials.
Komplexibildungsgleichgewichte und Redoxpotentiale des Systems Ag(II)/Ag(I) in Gegenwart von 2,2:6,2-Terpyridin in Wasser
Zusammenfassung Mit Hilfe derpH-metrischen Methode wurden die konditionalen Protonationskonstanten (=0.1) von 2,2:6,2-Terpyridin bestimmt: logK 1=4.93, logK 2=3.69. Es wurde auch die Zusammensetzung der Komplexe von Ag(II) und Ag(I) mit 2,2:6,2-Terpyridin(tp) bestimmt sowie die Gleichgewichte der komplexbildung beschrieben. Die Werte der Konditionalkomplexbildungskonstanten sind: für Ag(tp) 2 + :log01=5.79, log02=9.68, für Ag(tp) 2 2+ :log02=25.31 und für das Löslichkeitsprodukt Ag(tp)NO3:K SO –1 =4.08·10–5. Die in Komplexlösungen von Ag(II) und Ag(I) vorliegenden Redoxsysteme wurden mittels cyclischer Voltametrie und Coulometrie untersucht und die Formalpotentialwerte dieser Systeme in Wasser bestimmt.
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16.
Summary Complexes of manganese(II) and iron(II) picrates with various bidentate (L) and monodentate (L) heterocyclic bases have been synthesised; their compositions have been established as [ML3]A2 (1), [ML2 · 2 H2O]A2 (2), [ML6]A2 (3) and [ML4 · 2 H2O]A2 (4), where M = FeII and MnII, L = 2,2-bipyridyl (bipy) and 1,10-phenanthroline (phen) in (1), A = picrate anion; M = MnII, L = bipy and phen in (2); M = FeII, L = pyridine (py), 4-picoline (4-pic) and 3-picoline (3-pic) in (3); M = MnII, L = py, 4-pic, quinoline (quin) and 2,6-lutidine (2,6-lut) in (4) and also M = FeII, L = quin and 2,6-lut.  相似文献   

17.
1.4-Bis(4-hydroxy-1,2,5-trimethyl-4-piperidyl)-1.3-butadiyne has been synthesized from the individual isomers of 4-ethynyl-1,2,5-trimethyl-4-piperidol. Hydrogenation, bromination, and cleavage have given, respectively, 1,4-bis(4-hydroxy-1,2,5-trimethyl-4-piperidyl)butane, 1,4-bis(4-nydroxy-1,2,5-trimethyl-4-piperidyl)-1,2,3,4-tetrabromo-1, 3-butadiene, and 4-(1,3-butadiynyl)-1,2,5-trimethyl-4-piperidol.  相似文献   

18.
In aqueous and aqueous-ethanolic buffer solutions at pH<9, 2, 2-bifuryl and 2, 2-furoin give two-electron polarographic electroreduction waves, the half-wave potentials of which depend on the pH. The primary product of the electroreduction of 2, 2-bifuryl is trans-1,2-dihydroxy-1,2-bis(, -furyl)ethylene, which then rearranges into 2, 2-furoin. The anode-cathode wave of 2,2-bifuryl has been studied by means of a Kalousek commutator. It has been shown that the polarographic behavior of 2,2-bifuryl and 2, 2-furoin is similar to that of benzil and benzoin, but differs from the behavior of analogs of the pyridine series.  相似文献   

19.
Chlorination of the title compound gave 5- and 3-chloro-2-hydroxy-4,6-dimethoxyacetophenone. The nitration of its acetate, followed successively by reduction, diazotization, and reaction with cuprous chloride, gave the 3-substituted series, 2-acetoxy-4,6-dimethoxy-3-nitroacetophenone, 3-amino-2-hydroxy-4,6-dimethoxyacetophenone, and 3-chloro-2-hydroxy-4,6-methoxyacetophenone, respectively. The orientation of substituents in the products was proved. The amino and chloro members of the isomeric 5-substituted series were availablevia 2-hydroxy-4,6-dimethoxy-5-phenylazoacetophenone, the product of the reaction of the title compound with benzenediazonium chloride.
Nitrierung, Aminierung und Halogenierung von Di-O-methylphloracetophenon
Zusammenfassung Chlorierung der Titelverbindung gab 5- und 3-Chlor-2-hydroxy-4,6-dimethoxyacetophenon. Die Nitrierung des Acetats, gefolgt von Reduktion, Diazotierung und Reaktion mit CuCl ergab die 3-substituierte Reihe: 2-Acetoxy-4,6-dimethoxy-3-nitroacetophenon, 3-Amino-2-hydroxy-4,6-dimethoxyacetophenon und 3-Chlor-2-hydroxy-4,6-dimethoxyacetophenon. Die Orientierung der Substituenten wird diskutiert. Die Amino- und Chlorderivate der isomeren 5-substituierten Reihe sind über 2-Hydroxy-4,6-dimethoxy-5-phenylacetophenon zugängig, dem Produkt der Reaktion der Titelverbindung mit Phenyldiazoniumchlorid.
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20.
Conclusions A new coumarin, which has been called smyrniodidin, has been isolated from the roots ofSmyrniopsis aucheri acetoxy-1-methylethyl)-4-angeloyloxy-4,5dihydrofuro-2, 3: 7, 6-coumarin. Boiss. The NMR spectrum and a study of the saponification products of smyrnioridin have shown that it is 5-(1-  相似文献   

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