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1.
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   

2.
The correlations between the values of the lgK (K = stability constant of the lanthanide complex) and the reciprocal of the ionic radius 1/r or the sum of the ionization potentials 1 3 I for the lanthanide ions were reviewed for different ligands. A straight-line relationship (lgK – lgK)/lgK vs. (1/r – 1/r)/(1/r) or vs. ( 1 3 I1 3 I)/ 1 3 I was found within the tetrads La-Nd, Gd-Ho, and Er-Lu.
Bemerkungen zum periodischen Wechsel der Stabilitätskonstanten von Lanthaniden-Komplexen
Zusammenfassung Es wurde eine Übersicht der Korrelationen zwischen den Werten von logK (K = Stabilitätskonstante der Lanthanidenkomplexe) und den reziproken Ionenradien 1/r oder der Summe der Ionisierungspotentiale 1 3 I für die Lanthanidenionen für verschiedene Liganden gegeben. Dabei wurde eine lineare Korrelation für (lgK – lgK)/lgK gegen (1/r – 1/r)/(1/r) oder gegen ( 1 3 I1 3 I)/1/3 I innerhalb der Tetraden La-Nd, Gd-Ho und Er-Lu aufgefunden.
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3.
A method has been developed for the synthesis of 4-[2-(bromomethyl)phenyl] tetrahydro-2H-4-pyrancarbonitrile and a study was carried out on the reaction of this compound with primary amines, which, depending on the conditions, leads to either 4-[2-(R-aminomethyl)phenyl]tetrahydro-2H-4-pyrancarbonitriles or hydrobromides of 2-R-aryl-2,3,2,3,5,6-hexahydrospiro[isoquinoline-4(1H),4-pyran]-3-imines.Taras Shevchenko Kiev University, 252017 Kiev, Ukraine; e-mail: vkysil@mail.univ.kiev.ua. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1035–1041, August, 2000.  相似文献   

4.
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   

5.
2,2,4-Trichloro-6-phenyl-4,5-dipyrimidinyl, for which nucleophilic substitution with piperdine under various conditions was studied, was obtained from 2,2,4-trioxo-6-phenyl-1, 1,2,2,3,4-hexahydro-4,5-dipyrimidinyl. It is shown that there is an appreciable difference in the rates of substitution of the first, second, and third chlorine atoms, and this made it possible to obtain reaction products that contain one, two, and three piperidino groups. The chlorine atom in the 4 position is replaced initially, after which the chlorine atom in the 2 position undergoes substitution. The structures of the compounds were proved by chemical transformations and analysis of the PMR spectra.See [1] for communication 69.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 821–826, June, 1979.  相似文献   

6.
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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7.
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   

8.
On electrolysis mono- and bicyclic furfuryl-substituted alcohols undergo intramolecular alkoxylation, giving polycyclic spirans. Spiro[perhydrobenzofuran-2, 2-(5-methoxy, 5H)furan] and spiro[4H, 5H, 6H, 11H-naphtho-(,)-furan-2(3H)] [2-(5-methoxy, 5H)furan], hitherto not described, are prepared in this way. On catalytic hydrogenation they give the previously unknown spiro[perhydrobenzofuran-2, 2-tetrahydrofuran] and spiro[4H, 5H, 6H, 11H-naphtho-(,)-furan-2(3H)][2-tetrahydrofuran].For Part XXIX see [1].  相似文献   

9.
A convenient method has been developed for the synthesis of 5-methyl-2-desoxyuridines. Chlorination of 5-O-benzoyl-5-methyluridines with a mixture of Ph3P and CCl4 in DMF affords the 2-desoxy-2-chloro-derivatives, which are then reduced with tributyltin hydride. The crystalline 5-O-benzoyl-5-methyl-2-desoxyuridines were obtained in overall yields of 40–60%. In a similar way, 5-O-benzoyluridine has given 5-O-benzoyl-2-desoxyuridine.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 246–248, February, 1989.  相似文献   

10.
Infrared studies of the interaction of NO with CuY–A zelites have been made over the temperature range from –100°C to 400°C. Several forms of NO adsorption have been found, in particular, a stable cis-dimer at low temperatures.
- (–100+400°C) NO CuY–A . NO, ë - .
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11.
    
A universal key component is proposed for the preparation of oligonucleotides with 3- and 5-terminal phosphate groups — 2,3-dibenzoyluridin-5-yl (4-chlorophenylphosphate) (pU(Bz)2), which is a potential source of the phosphate group. The condensation ofpU(Bz)2 with the 5-OH or the 3-OH group of a protected oligonucleotide leads to the formation of oligodeoxyribonucleotides with 5- or 3-terminal uridine, respectively. The oxidation of the 2,3-cis-glycol group of the terminal uridine unit followed by -elimination forms oligodeoxyribonucleotides with terminal phosphate groups.M. V. Lomonosov Moscow State University. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 731–734, September–October, 1987.  相似文献   

12.
A method is suggested for studying the kinetic parameters of two-stage reactions from thermoanalytical experimental data. The method allows determination of the kinetic characteristics of the process on the basis of integral thermoanalytical data, without separation of the individual stages. Parallel, independent and successive reactions taking place under isothermal and non-isothermal conditions are considered.
Zusammenfassung Eine Methode zur Untersuchung der kinetischen Parameter von Zweistufenreaktionen unter Verwendung experimenteller thermoanalytischer Daten wird vorgeschlagen. Die Methode ermöglicht, die kinetischen Kennwerte des Prozesses basierend auf integralen thermoanalytischen Werten ohne Trennung der individuellen Schritte zu bestimmen. Unter isothermen und nichtisothermen Bedingungen parallel, unabhängig voneinander und nacheinander verlaufende Reaktionen werden diskutiert.

. , . , , .
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13.
Research on synthesis of polycyclic spirans of the 1, 6-dioxaspiro-[4, 4]nonane group is continued. Electrolysis of methanol solutions of 2-furylcyclopentanol, 2-(5-methyl-furfuryl)cyclopentanol, and 2-furfuryl-1-indanol, gives, by intramolecular alkoxylation, spiro{perhydrocyclopenta[b]furan-2, 2-(5dihydrofuran)}, spiro{perhydrocyclopenta[b]furan-2, 2-(5-methoxy-5-methyl-2, 5-dihydrofuran)}, and spiro{2, 3, 3a, 8b-tetrahydro-4H-indeno[1, 2-b]furan-2, 2-(5-methoxy-2, 5-dihydrofuran)}, hitherto undescribed in the literature. Depending on the conditions, catalytic hydrogenation of these gives: spiro{perhydiocyclopenta[b]furan-2, 2-(5-methoxytetrahydrofuran)}, spiro{2, 3a, 8b-tetrahydro-4H-indeno[1, 2-b]furan-2, 2-(5-methoxytetrahydrofuran)}, spiro{perhydrocyclopenta[b]furan-2, 2-tetrahydrofuran}, and spiro{2, 3, 3a, 8b-tetrahydro-4H-indeno[1, 2-b]furan-2, 2-tetrahydrofuran}.For Part XXXI see [1].  相似文献   

14.
Methyl 1-aryl-3-aroyl-4,5-dioxo-4,5-dihydro-1H-pyrrole-2-carboxylates react with N-substituted 3-amino-5,5-dimethyl-2-cyclohexenones to give 4-hydroxy-1-aryl-3-aroyl-6,6-dimethyl-1, 2,3,4,5,5,6,7-octahydro-1H,2H-indole-3-spiro-2-pyrrole-2,4,5-triones. The structure of the products was proved by the X-ray diffraction data for the 1-cyclohexyl derivative.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 40, No. 12, 2004, pp. 1840–1845.Original Russian Text Copyright © 2004 by Bannikova, Maslivets, Aliev.For communication XLVIII, see [1].  相似文献   

15.
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   

16.
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   

17.
Summary Cobalt(II) and nickel(II) halide complexes of the ligands 2-(2-methyl-8-quinolyl)benzoxazole (mqbo), 2-(2-methyl8quinolyl)benzimidazole (mqbi) and 2-(4-methyl-8-quinolyl)benzimidazole (mqbi) were synthesized and characterized by analytical, thermogravimetric, conductivity and magnetic data, and i.r. and electronic spectra.The ligands are bidentate N-donors yielding complexes where the coordination geometry depends on the metal ion and steric hindrance. All the cobalt complexes have formula [CoL2X2] and distorted tetrahedral geometry. Different types of nickel compounds were obtained: i) complexes of formula NiLX2 · n H2O (or EtOH) (L = mqbo or mqbi; n=0–1.5) which arepseudo-tetrahedral or five-coordinate and ii) complexes NiL2X2 · n H2O (L = mqbi, n=3 or 4) where the metal is bound to four nitrogen atoms and the overall coordination geometry is tetragonal. The structural changes occurring after removal of water or alcohol from the complexes are also reported.  相似文献   

18.
Summary Complexes of general formula MLmCl2 · nH2O, where M=cobalt(II) or nickel(II); L=2-(4-methyl, 2-pyridyl)-benzimidazole (mpbi), 2-(4-methyl, 2-pyridyl)benzothiazole (mpbt), 2-(4-methyl, 2-pyridyl)benzoxazole (mpbo), 2-(4-methyl, 2-quinolyl)benzoxazole (mqbo), or 2-(4-methyl, 8-quinolyl)benzoxazole (mqbo); m=1,2; n=0–3, were prepared and characterized by t.g.a., conductance and magnetic measurements, i.r. and diffuse-reflectance electronic spectra.All the ligands behave as bidentate and coordinate through the pyridine- and isoxazole-nitrogen atoms.The nickel complexes have distorted octahedral or fivecoordinate structures. The cobalt complexes arepseudo-tet- rahedral except Co(mpbo)2Cl2·2H2O where the metal is six-coordinate.  相似文献   

19.
Summary. ESR and ENDOR spectra are reported of several symmetrical substituted N,N,N,N-tetraalkyl-p-phenylenediamine radical cations in solution. Different N,N-alkyl substituted para-phenylenediamines, like the ethyl, n-propyl, and iso-propyl derivative are compared with the parent N,N,N,N-tetramethyl-p-phenylenediamine (Wursters Blue Cation). N,N,N,N-Tetrabenzyl-p-phenylenediamine, 1,4-dipyrrolidinylbenzene, and N,N-bis[4-(dimethylamino)phenyl]piperazine are additionally investigated. Experimental and calculated hyperfine coupling constants are compared. Characteristic UV-VIS data and redox potentials in acetonitrile are reported, together with the syntheses of the compounds.  相似文献   

20.
Conclusions The action of selenium dioxide in dioxane on the ethyl ester of-ketodebydrodesthiobiotin and of lead tetraacetate in glacial acetic acid on its N,N-diacetyl derivative give the corresponding ethyl esters of,-dioxodehydrodesthiobiotin and-oxo--acetoxy-N,N-diacetyldehydrodesthiobiotin.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2025–2028, September, 1972.  相似文献   

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