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821.
Zusammenfassung Bei Einwirkung von H2S und Aminen bzw. NH3 auf Acetophenon bzw. Propiophenon entstehen in Gegenwart elementaren Schwefels Bis-[1-phenylalkyl-(1)]-polysulfide, ohne Zusatz von Schwefel in der Hauptsache Bis-[1-phenylalkyl-(1)-]-disulfide. Die Struktur der linearen Di- und Polysulfide wurde durch Chlorolyse und Vergleich mit auf anderem Wege hergestellten Polysulfiden ermittelt.Die Reaktionen verlaufen über Ketimine als Zwischenstufe. Diese Intermediärprodukte wurden synthetisiert und geben bei der H2S-Behandlung gleichfalls Bis-[1-phenylalkyl-(1)]-disulfide. Die Frage des Auftretens von Enaminen bei Verwendung von Morpholin als Aminkomponente wird diskutiert.Teil der Dissertation vonK. Halcour, T. H. Aachen, 1961. 相似文献
822.
A. P. Kilimov M. A. Svechnikova V. I. Shevchenko V. V. Smirnov F. V. Kvasnyuk-Mudryi S. B. Zotov 《Chemistry of Heterocyclic Compounds》1967,3(2):467-471
Data for the characteristic bands of cyclic ethers are reviewed. The infrared spectra of a number of 2-mono- and 2, 5-di-substituted
derivatives of tetrahydrofuran are investigated. Absorption bands at about 900 cm−1 are related to pulsation vibrations, and those at about 1200 cm−1 to antisymmetric skeletal vibrations, of the tetrahydrofuran ring. It is shown that to confirm the presence of a tetrahydrofuran
ring in a molecule, it is necessary to take into account not only the band of valence antisymmetric vibrations of the group
C-O-C (ν
C-O-C
as
1075 cm−1), but also bands due to ring pulsation vibrations (ring symmetric valence vibrations ν
sk
s
∼ 900 cm1). 相似文献
823.
The effect of substituted hydroxybenzophenone, benzotriazole and organic metal complexes on the photooxidation of PP films has been studied. It has been established that NiDBTC added in 1.0 wt. % is the most effective photostabilizer.While in the case of other stabilizers there is a slight increase in the Co content even during the induction period, with the application of NiDBTC practically no oxidation can be observed before the stabilizer completely disappears. This means that NiDBTC inhibits the photooxidation of the polymer even in low concentration.
, - . , Ni, 1,0 . %. . , Ni , . , Ni .相似文献
824.
Rh(π-C3H5)(PF3)3 (I), reacts with trifluoroacetic acid to form propene and [Rh(CF3COO)(PF3)2]2 (II). I reacts with t-butyl bromide to give [RhBr(PF3)2]2 and a mixture of propene and 2-methyl-1-propene and with n-propyl bromide to give propene and [RhBr(PF3)2]2. Rh(π-C3H5)(PPh3)2 (III), and t-butyl bromide yield propene and 2-methyl-1-propene. In these reactions a mechanism involving β-hydrogen abstraction and hydrogen migration via the metal to carbon is proposed. When III reacts with Me3SnCl the Me3Sn—moiety migrates intact to the π-allyl group. I reacts with acetyl chloride to give propene, [RhCl(PF3)2]2 and the carbonyl rhodium complex Rh2Cl2(PF3)3(CO). II does not apparently undergo phosphine ligand exchange unlike the analogous halogeno-bridged dimers. 相似文献
825.
The optically active methylphenyl-α-naphthylsilane racemises quickly in tetrahydrofuran in the presence of LiAlH4.Kinetic results show a different behaviour of the hydride depending on its concentration. Activation parameters have been obtained and mechanisms proposed. 相似文献
826.
. .
Air regeneration of a coked silica-alumina catalyst for the synthesis of pyridines and picolines has been studied. The results are discussed in relation to changes in porosity and structure occuring during thermal treatment.相似文献
827.
The structure of 2,7-dimethyl-3-acetylquinoxaline was proved by conversion of it to 2,7-dimethyl-1,2,3,4-tetrahydroquinoxaline. 2,7-Dimethylquinoxaline and 2-methyl-3-acetyl-6-aminoquinoxaline were synthesized.See [1] for communication II.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1700–1701, December, 1972. 相似文献
828.
M. F. Jarrold U. Ray Y. Ijiri 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1991,19(4):337-342
The chemical reactions of size selected silicon cluster ions (containing up to 70 atoms) have been studied with a number of different reagents using injected ion drift tube techniques. Both kinetic and equilibrium measurements have been performed as a function of temperature, and the influence of cluster annealing on chemical reactivity explored. Unlike metal clusters, where bulk behavior appears to be approached with around 30 atoms, large silicon clusters (n up to 70) are much less reactive than bulk silicon surfaces. These results suggest that the clusters in the size range examined here are not small crystals of bulk silicon, but have compact, high coordination number structures with few dangling bonds. 相似文献
829.
The system POCl3–NaAlCl4 was investigated by measuring the conductivity and the Raman and NMR spectra (27Al, 23Na and 31P) as a function of the mol fraction x of NaAlCl4 in POCl3. Additionally, Raman spectra of POCl3 solutions of NaFeCl4, LiAlCl4, LiFeCl4, and KAlCl4 were recorded. In solutions containing Li+ or Na+ ions a liquid to solid (or jelly) phase transition was observed under certain conditions, dependent on salt concentration and temperature. Observed changes in the Raman spectra of the electrolyte solutions in comparison to the pure solvent POCl3 demonstrate the existence of interactions. Clearly, the POCl3 eigenfrequencies and hence the molecules are pertubed. The formation of [M(POCl3)4]+ complexes (M = Li, Na) can be deduced from the Raman measurements. NMR investigations support this conclusion. For assigning of Raman spectra, (Li+, K+) cation and ([FeCl4]?, [SbCl6]?) anion substitutions were employed. 相似文献
830.
N. F. Pedchenko N. D. Trusevich V. F. Lavrushin 《Chemistry of Heterocyclic Compounds》1974,10(4):418-420
The shifts of the stretching vibrations of the hydroxyl groups of phenol and pentachlorophenol during the formation of intermolecular hydrogen bonds with 2-thienyl phenyl ketones containing substituents in the benzene ring were measured. A correlation dependence between theD
OH values and + substituent constants was established.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 482–485, April, 1974. 相似文献