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61.
Half-sandwich [η51N-C5Me4CH2-(2-C5H4N)]MCl3 (M = Ti (4), Zr (5)) and sandwich [η5-C5Me4CH2-(2-C5H4N)][η5-C5Me5]ZrCl2 (6) ring-peralkylated complexes have been prepared and characterized. Evidence of the intramolecular coordination of the side-chain pyridyl group both in 4 and 5 in solutions is provided by NMR spectroscopy data. Crystal structure of an adduct 5-py with one molecule of pyridine has been established by X-ray diffraction analysis.  相似文献   
62.
The reaction of trifluoromethyl-containing enones with thiophenol derivatives has been studied. Reactions with 4-methylthiophenol proceed with the formation of either ketosulfides or a pyran derivative. Reactions of trifluoromethyl-containing enones with 2-mercaptobenzaldehyde lead to 3-trifluoroacetyl-substituted 2H-thiochromenes. M. V. Lomonosov Moscow State University, Moscow 119899, Russia N. S. Kurnakov Institute of General and Inorganic Chemistry, Russian Academy of Sciences, Moscow 117907, Russia. Department of Chemistry, University of Durham, South Road, Durham, Great Britain, DH1 3LE. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 618–626, May, 1999.  相似文献   
63.
The nonlinear response of a CO2 laser to biharmonic loss modulation was theoretically investigated for tuning of the radiation frequency within the limits of the amplification band. It is shown that the value and form of the amplitude-detuning characteristic (and, consequently, the temporal and energy parameters of the laser radiation) can be controlled within sufficiently wide limits by changing the modulation frequency and the phase shift of oscillations. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 66, No. 1, pp. 43–47, January–February, 1999.  相似文献   
64.
Reactions of Si- and Ge-substituted alkynes with KICl2 were investigated. (1-Germatranyl)-phenylacetylenes and (triphenylsilyl)phenylacetylene gave Z-iodochloroalkenes with chlorine and phenyl groups attached to the same carbon atom. Adduct structures were confirmed by X-ray diffraction studies. © 2004 Wiley Periodicals, Inc. Heteroatom Chem 15:169–174, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20001  相似文献   
65.
Butadienyl dyes of the benzothiazole series with various fragments of benzocrown ethers 1a – c were synthesized for the first time. The structures and spectral properties of crown‐containing butadienyl dyes and their complexes with alkali and alkaline‐earth metal cations were studied by X‐ray diffraction analysis and 1H‐NMR, UV/VIS, and resonance Raman spectroscopy. To interpret the experimental results, quantum‐chemical calculations were performed. In the case of Sr2+ and Ba2+ ions, the formation of strong sandwich complexes [M( 1b )2]2+ of an unusual structure involving stacking interactions was established; the dye molecules are arranged one above another in the complex according to the ‘head‐to‐head' pattern.  相似文献   
66.
67.
An unexpectedly high yield of anhydroindanone‐1 disulfide (1) was obtained by reaction of Lawesson's reagent with indanone‐1. The molecular structure of 1 was established by X‐ray diffraction. A possible mechanism of the reaction is discussed. © 1999 John Wiley & Sons, Inc. Heteroatom Chem 10: 369–371, 1999  相似文献   
68.
The reaction of dialkanolamines RN(CH2CH2O)(CHR’CHR’OH) (R = Me, Ph, PhCH2; R’ = H, Ph) with tetraethoxygermane gives either 2,2-diethoxy-1,3,6,2-dioxazagermocanes RN(CH2CH2O)(CHR’CHR’O)Ge(OEt)2 or 1,7,9,15-tetraoxa-4,12-diaza-8-germaspiro[7.7]pentadecanes [RN(CH2CH2O) (CHR’CHR’O)]2Ge depending on the reactant ratio. The chemical behavior of the obtained compounds in substitution reactions at germanium was studied. The product structure was confirmed by elemental analysis data and 1H, 13C, and 19F NMR spectroscopy. The cyclotrigermanoxane [MeN(CH2CH2O)2GeO]3 was studied by X-ray diffraction.  相似文献   
69.
The reaction of palladium carbonyl carboxylates Pd6(CO)6(RCOO)6 with gaseous nitrogen monoxide was investigated. These clusters were found to promote the NO disproportionation into N2 and NO2 under mild conditions. The reaction is accompanied with the oxidation of coordinated carbon monoxide. These processes result in unusual eight-nuclear palladium carboxylate clusters Pd8(CO)4(NO2)4(RCOO)8.  相似文献   
70.
Thermolysis of 7-azido-8-(2H-1,2,3-triazol-2-y1)-1,2,3,4-benzotetrazine 1,3-dioxide and 7-azido-8-(l H-1,2,3-triazol-l-yl)-1,2,3,4-benzotetrazine 1,3-dioxide afford new heterocyclic systems, viz., 7,11-dehydro-7H, 11H [1,2,3]triazolo[l′,2′:2,3][1,2,3]triazolo[4,5-f]-[1,2,3,4]benzotetrazine 1,3-dioxide and 7,9-dehydro-7 H, 9H [1,2,3]triazolo[2′,1′:2,3]-[1,2,3]triazolo[4,5-f][1,2,3,4]benzotetrazine 1,3-dioxide, respectively, and their thermal stability has been studied.  相似文献   
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