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51.
IR spectra of M(1,4-diaminobutane)Ni(CN)4° 1.5C6H6 (M = Mn, Fe, or Co), and IR and Raman spectra of M(1,4-diaminobutane)Ni(CN)4° 1.5C6H6 (M = Ni or Cd) clathrates are reported. The spectral features suggest that the compounds are similar in structure to the Hofmann-dabn-type clathrates.  相似文献   
52.
Cationic arene complexes [Cb*Co(naphthalene)]+ (2, Cb* = C4Me4) and [Cb*Co(phenanthrene)]+ were synthesized by the reactions of [Cb*Co(MeCN)3]+ with arenes. The [Cb*Co(anthracene)]+ complex was synthesized by the abstraction of the iodide ion from [Cb*CoI]2 by TIBF4 in the presence of anthracene. Complex 2 exchanges the naphthalene ligand for other arenes at room temperature. Dedicated to Academician G. A. Abakumov on the occasion of his 70th birthday. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1861–1863, September, 2007.  相似文献   
53.
Merits and drawbacks of known carbon-carbon linking procedures are outlined. Two novel methods are discussed in some detail: the copper-catalyzed alkylation of Grignard reagents and reactions with allylpotassium compounds. Both methods provide a very efficient access to saturated, unsaturated, as well as functionally substituted hydrocarbons and moreover permit an astonishing degree of regio- and stereoselective control of olefin synthesis.  相似文献   
54.
The reaction of 1-alkynylcyclobutanols with aryl iodides in the presence of Pd(OAc)2 and Et3N in acetonitrile at 80°C for 24 h gives 2-disubstituted methylenecyclopentan-1-ones in modest to good yields. The tandem insertion-ring expansion process proceeds via the formation of an alkynyl π-complex, followed by migration of a carbon-carbon bond of the tert-alkanol to form the cyclopentanones stereoselectively.  相似文献   
55.
The crystal and molecular structures of the products of the halogenation of the dimorpholide of ethoxyvinylphosphonic acid were determined by the method of x-ray structure analysis. It was established that (dimorpholinophosphoryl)chloroacetaldehyde only exists in the crystals as the Z-enol [(Z)-1-hydroxy-2-(dimorpholinophosphoryl)-2-chloroethene] with intra- and intermolecular H-bonds (=CH...O=P and OH...O=P). The (dimorpholinophosphoryl)dibromomethane forms centrosymmetric eight-membered cyclic dimers in the crystals due to intermolecular CH...O=P H-bonds. The structure of the morpholine and phosphoryl groups in both compounds was discussed.A. E. Arbuzov Institute of Organic and Physical Chemistry, Kazan' Scientific Center, Russian Academy of Sciences, 420083 Kazan'. Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 12, pp. 2730–2737, December, 1992.  相似文献   
56.
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   
57.
Catalytic cycloalumination of cyclonona-1,2-diene upon treatment with Et3Al and EtAlCl2 in the presence of Cp2ZrCl2, leading to 10-ethyl-10-aluminabicyclo[7.3.01,9]dodec-8-ene (1) and 11-ethyl-11-aluminatricyclo[10.7.01,12.02,10]nonadeca-9,12-diene, respectively, was accomplished in high yields. A possibility for the selective transformation of compound 1 to 1-allyl-9-(pent-4-enyl)cyclonon-1-ene and 10-hydroxybicyclo[7.3.01,9]dodec-8-ene in one preparative step was demonstrated. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2156–2159, November, 2007.  相似文献   
58.
The syn-isomer of 1,8-bis(4,4′-diisopropyl-9,9′-diacridyl)naphthalene, 1, has been prepared by two consecutive Pd(PPh3)4-catalyzed Stille cross-coupling steps. This highly congested sensor undergoes Fe(III)-selective fluorescence quenching in water/acetonitrile even in the presence of excess of other metal ions.  相似文献   
59.
60.
The influence of mitoxantron (M) and benz(a)pyrene (BP) on chromatin DNA in composition of spleen and liver tissues and cells of BALB/c mice were studied using a high-sensitive differential scanning microcalorimeter. It was established that BP can cause a) the specific breaks in inactive chromatin DNA chain and unfolding of the whole domain (a loop of chromatin) which should lead to uncontrolled genome activation; b) the breaks in the DNA double-helix creating short duplexes.M at low doses, interacting with naked linker DNA of tumor restores the chromatin structure, at high doses or at repeated injections,M causes the disturbance of chromatin structure.  相似文献   
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