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41.
Herbert Schumann Kerstin Zietzke Frank Erbstein Roman Weimann 《Journal of organometallic chemistry》1996,520(1-2):265-268
LnCl3 reacts with Na(C5Me41Bu) in THF to form the organolanthanoid chlorides [(C5Me41Bu)2LnCl(THF)] (Ln = La (1a), Lu (1b)). Compounds 1a and 1b yield in reaction with NaO2CCH3 the monomeric organolanthanoid acetates [(C5Me41Bu)2LnO2CCH3] (Ln = La (2a), Lu (2b)). The single crystal X-ray structure analysis of 2b as well as the cryoscopic molecular weight investigation of 2a verify the monomeric structure of these complexes. 相似文献
42.
The complexing processes in the CuII–1,2-diaminoethanedithione-1,2–ethanedione-1,2 and CuII–1,2-diaminoethanedithione-1,2–butanedione-2,3 triple systems occuring in the copper(II)hexacyanoferrate(II) gelatin-immobilized
matrix in contact with aqueous alkaline solutions (pH~12) containing 1,2-diaminoethanedithione-1,2 and ethanedione-1,2 or
butanedione-1,2 under room temperature, and between MCl2, 1,2-diaminoethanedithione-1,2 and ethanedione-1,2 or butanedione-1,2 in the ethanol solutions, upon heating up to ~80 °C,
have been studied. In both systems indicated, template synthesis occurs in the gelatin-immobililized matrix but does not occur
in the ethanol solution. As a result of template synthesis, macrocyclic CuII chelates with 2,7-dithio-3,6-diazaoctadien-3,5-dithioamide-1,8 and its 4,5-dimethylsubstituted derivative are formed in the
gelatin-immobililized matrix. 1,2-diaminoethanedithione-1,2 and ethanedione-1,2 or butanedione-2,3 are the ligand synthons
in the processes indicated. 相似文献
43.
E. Gilbert G. V. Veriovkin V. A. Mikhailov N. I. Antipov V. N. Nikitin 《Journal of Radioanalytical and Nuclear Chemistry》1977,38(1-2):147-154
Two previously developed methods of noble metal neutron activation (NA) determination have been applied for the analysis of
technological materials. While comparing the data obtained by both methods with those obtained in Central Chemical Laboratory
the systematical discreapences have been shown to be absent. A new method of Pd, Au, Pt and Ir NA determination in natural
and technological specimens based on the selective extraction of Pd and Au preliminary to irradiation has been developed.
Results of the analysis of “Glomar Cellenger”'s deep-water drilling samples are discussed obtained by this method. 相似文献
44.
Mikhailov S. N. Kritsyn A. M. Kolobushkina L. I. Florent'ev V. L. 《Russian Chemical Bulletin》1975,24(4):829-830
Conclusions We synthesized nine analogs of dinucleoside monophosphates that contain 9-(2-hydroxyethyl)adenine, 9-(3-hydroxypropyl)adenine, and 9-(4-hydroxybutyl)adenine as the 3 residue, and the natural nucleosides: uridine, cytidine, adenosine, guanosine, and inosine as the 5 residue.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 915–916, April, 1975. 相似文献
45.
Tat'yana T Kucherenko Roman Gutsul Vladimir M Kisel Vladimir A Kovtunenko 《Tetrahedron》2004,60(1):211-217
Previously unknown 3-arylamino-1,2-dihydro-1-isoquinolones were obtained by condensation of 2-cyanomethylbenzoic acid with arylamines. Isonicotinoylation of the compounds was shown to proceed at the carbon atom in the 4-position to give 3-arylamino-4-isonicotinoyl-1,2-dihydro-1-isoquinolones which were quaternized with alkylating agents and formed the corresponding pyridinium salts. Deprotonation of the latter induced intramolecular conjugated addition with the pyrrole ring closure and formation of spiro compounds. The structure of the products was confirmed by NMR, IR and UV spectroscopy and by synthesis of the model compound, 3-(4-tolyl)-2,3,4,5-tetrahydro-1H-pyrrolo[2,3-c]isoquinoline-1,5-dione. 相似文献
46.
Haiwen Zhang David W. Norman Tracey M. Wentzell Alison M. Irving Janet P. Edwards Susan L. Wheaton Christopher M. Vogels Stephen A. Westcott Felix J. Baerlocher Andreas Decken 《Transition Metal Chemistry》2005,30(1):63-68
Reactions of salicylaldehydes with boronate ester derivatives of aniline have been examined. Addition of these Schiff base ligands to palladium acetate or Na2PdCl4 afforded novel boron-containing trans-bis(N-arylsalicylaldiminato) palladium complexes.Condensation of salicylaldehyde (2-HOC6H4C(O)H) with H2NC6H4Bpin (pin=1,2-O2C2Me4) afforded the boron-containing Schiff bases, 2-HOC6H4C(H)=NC6H4Bpin (1–3a). Similar reactivity with 2-hydroxy-5-nitrobenzaldehyde and 2-hydroxy-1-naphthaldehyde gave the corresponding Schiff bases (1-3b) and (1-3c), respectively. Reaction of Schiff bases (2) and (3) with palladium acetate or Na2PdCl4 afforded complexes of the type PdL2
(4,5), where L=deprotonated Schiff base. The molecular structure of the nitro-salicylaldehyde 4-Bpin palladium complex (5b) was characterized by an X-ray diffraction study. All new palladium compounds have been characterized fully and tested for their antifungal activity against Aspergillus niger and Aspergillus flavus. 相似文献
47.
An electrospray ionization (ESI) ambient pressure ion-mobility spectrometer (APIMS) interfaced to an orthogonal reflector time-of-flight mass spectrometer (TOFMS) was evaluated for the first time as a detector for the identification of phenylthiohydantoin (PTH)-derivatized amino acids, the final products in the Edman sequencing process of peptides and proteins. The drift and flight times of the twenty common PTH amino acids were characterized by a well-defined 2-D mobility/mass spectral pattern. The combination of mobility/mass modes of analysis gave rise to a unique trend-line formation for the series of PTH amino acids. In addition, each PTH amino acid had a unique reduced mobility constant K(o), thus enabling the differentiation of all the amino acid derivatives including the PTH-leucine and PTH-isoleucine isomers. More importantly it was shown that it was possible to resolve a complete reference mixture of PTH amino acids in a single experimental run in less than 1 min. Detection limits for the PTH amino acids were found to range from 1.04 to 3.52 ng; indicating that the limits of detection were less than 17.0 pmol for all of the PTH amino acids. 相似文献
48.
The coordination compound [Co(C10H7COO)2(H2O)3]2n
· 4nH2O was prepared by the reaction of 1-naphthoic acid and cobalt(II) acetate tetrahydrate in basic solution, and was fully characterized
by X-ray diffraction, element analysis, FTIR, TG-DTA and luminescent spectra. In the crystal the six-coordinated Co(II) centers
are linked into one-dimensional zigzag chains by water molecules, which are further assembled into a two-dimensional network through weak inter-chain C–H···π interactions.
The solid complex exhibits favorable fluorescent properties similar to those of free ligand at room temperature, which can
be assigned to the intraligand electronic transfer. 相似文献
49.
S. V. Volkov S. V. Kutyakov A. N. Levov E. I. Polyakova Le Tuan An S. A. Soldatova P. B. Terentiev A. T. Soldatenkov 《Chemistry of Heterocyclic Compounds》2007,43(10):1260-1268
It has been established that on heating, 3-benzoyl-4-hydroxy-1-methyl-4-phenylpiperidine is ring-opened in the presence of
arylamines by a type of retroaldol reaction, with subsequent transamination of the intermediate Mannich base and the formation
of 3-arylamino-1-oxo-1-phenylpropanes. When using arylhydrazines this γ-piperidol is recyclized with the formation of 1,3-diarylpyrazoles
and their 4,5-dihydro derivatives. The mass spectral behavior of a series of 3-arylamino-substituted 1-phenylpropanones has
been studied.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1486–1495, October, 2007. 相似文献
50.
Attila R. Imre W. Alexander Van Hook Bong Ho Chang Young Chan Bae 《Monatshefte für Chemie / Chemical Monthly》2003,134(12):1529-1539
Summary. Upper critical solution temperatures (UCSTs) for liquid–liquid demixing in a set of mixtures of linear alkanes (pentane (N
1=5) to pentacontane (N
1=50)) with an oligostyrene (1241amu, N
2=12) are reported. We find strong correlation between the Hildebrand solubility parameters of the alkanes and the UCST. Correlations are developed which enable predictions concerning the miscibility of mixtures of compounds with longer chains. 相似文献