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1.
S. Yu. Kukushkin P. Yu. Ivanov L. M. Alekseeva V. I. Levina K. I. Kobrakov N. B. Grigor'ev V. G. Granik 《Russian Chemical Bulletin》2005,54(8):1887-1891
The half-wave potentials of polarographic reduction of the carbonyl group in unsubstituted and N-methyl- and N-phenylsulfonyl-substituted 1- and 4-oxotetrahydrocarbazoles and their reactivities in reactions with nucleophilic (NaBH4, malonodinitrile, and cyanoacetamide) and electrophilic (DMF dimethyl acetal) reagents were compared. 4-Oxotetrahydrocarbazoles
are much less reactive than 1-oxotetrahydrocarbazoles.
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Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1832–1836, August, 2005. 相似文献
2.
V. A. Sedavkina V. A. Morozova A. Yu. Egorova R. G. Savkin 《Russian Chemical Bulletin》1995,44(10):1914-1916
Treatment of 5-alkyl-3H-furan-2-ones and 5-alkyl-3H-thiophen-2-ones with dichlorocarbene under conditions of phase-transfer catalysis at 20–90 °C results in insertion of the carbene at the C=C bond followed by skeletal rearrangement.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1995–1997, October, 1995. 相似文献
3.
The intramolecular electrophilic substitution in 6-functionalized 1,3-dimethyl-1H-pyrrolo[3,4-d]pyrimidine-2,4(3H,6H)-diones was used for the synthesis of pyrimido[4′,5′:3,4]-pyrrolo[1,2-a]quinoxaline-8,10(7H,9H)-dione, pyrimido[4′,5′:3,4]pyrrolo[2,1-c][1,2,4]benzo-triazine-8,10(7H,9H)-dione, and 2H-pyrimido[4′,5′:3,4]pyrrolo[1,2-a]indole-2,4,11(1H, 3H)-trione derivatives.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2180–2185, December, 2006. 相似文献
4.
Beresnev D. G. Rusinov G. L. Ponomareva A. Yu. Chupakhin O. N. 《Russian Chemical Bulletin》2003,52(10):2161-2166
Recyclization of the addition products of alkylureas to 3-aryl-1,2,4-triazin-5(2H)-ones affording 1,2,4-triazole derivatives was found to occur in Ac2O. 相似文献
5.
Oxidative amination of 3-chloro-6,8-dimethylpyrimido[4,5-c]pyridazine-5,7(6H,8H)-dione with primary alkylamines and potassium amide in liquid ammonia gives rise to the corresponding 4-amino derivatives as the major products. The reactions with acyclic secondary amines are accompanied by annelation of the pyrrole moiety to the starting heterosystem to form 1-R-3-R"-6,8-dimethylpyrrolo[2",3";3,4]pyrimido[4,5-c]pyridazine-7,9(6H,8H)-diones. The reaction with piperidine as the aminating agent occurs exclusively as aminodehalogenation. The Sonogashira cross-coupling of 4-amino-3-chloro-6,8-dimethylpyrimido[4,5-c]pyridazine-5,7(6H,8H)-diones with terminal alkynes affords 1-R-2-R"-6,8-dimethylpyrrolo[3",2";3,4]pyrimido[4,5-c]pyridazine-7,9(6H,8H)-diones. 相似文献
6.
Summary The reaction of 2-ary-5-hydroxy-3(2H)-pyridazinones (1a, b) with bromine yields the 4-bromo derivatives2a, b and with sulfuryl chloride the chloro compounds3a, b are obtained. However, with an excess of chlorine or sulfuryl chloride the 4,4-dichloro-pyridazine-dione4 is produced. Hydrolysis of4 leads to5, and in a similar manner the open chain hydrazone8 is obtained from the carboxylic acid6.
Pyridazine mit Heteroatom-Substituenten in Stellung 3 und 5, 7. Mitt. Halogenierung von 2-Aryl-5-hydroxy-pyridazin-3(2H)-onen in 4-Stellung
Zusammenfassung Die Reaktion von 2-Aryl-5-hydroxy-pyridazin-3(2H)-onen (1a, b) mit Brom liefert die 4-Bromderivate2a, b, während mit Sulfurylchlorid3a, b erhalten werden. Ein Überschuß von Sulfurychlorid oder Chlorgas gibt jedoch das 4,4-Dichlor-pyridazin-dion4. Die Hydrolyse von4 führt unter Ringöffnung und Decarboxylierung zu5. In analoger Weise gibt die freie Carbonsäure6 das Hydrazon8.相似文献
7.
A. I. Rakhimov E. S. Titova R. G. Fedunov V. A. Babkin 《Chemistry of Heterocyclic Compounds》2008,44(6):700-708
The nucleophilic substitution of halogen (chlorine, bromine, and iodine) in alkyl and benzyl halides has been effected in
aqueous dioxane media with S-and O-anions generated from 4-hydroxy-2-mercapto-6-methylpyrimidine. Under these conditions replacement
of halogen proceeds by an SN2 mechanism and the reactivity of S-anions is 10 times greater than that of O-anions, which is in agreement with the results
of ab initio quantum-chemical calculations of the electronic structure and total energy of transition states, carried out
within the framework of the restricted Hartree-Fock method, basis 6-31G**.
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Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 874–883, June, 2008. 相似文献
8.
N. V. Kolotova V. O. Koz'minykh E. V. Dolbilkina E. N. Koz'minykh 《Russian Chemical Bulletin》1998,47(11):2246-2248
Aroylpyruvic acids and their methyl esters react witho-aminophenyldiphenylmethanol to form 4-aryl-2-[2-(1-hydroxydiphenylmethyl)phenylamino]-4-oxobut-2-enoic acids and their esters.
The α-enamino acids obtained undergo intramolecular heterocyclization in the presence of Ac2O to affort substituted 4,5-dihydrobenzo[e][1,4]oxazepin-3(1H)-ones. The reaction of 5-arylfuran-2,3-diones witho-aminophenyldiphenylmethanol leads to products of decyclization, 2-(1-hydroxydiphenylmethyl)phenylamides of 4-aryl-2-hydroxy-4-oxobut-2-enoic
acid, which upon heating in AcOH or Ac2O yield 3-aroylacetyl-1,1-diphenyl-1H-benzo[d][1,3]oxazines.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2317–2319, November, 1998. 相似文献
9.
Condensation of 4-bromobenzaldehyde, urea, and 4-alkyl-substituted acetophenones gave substituted hexahydro-1H,8H-pyrimido[4,5-d]pyrimidin-2,7-diones or 1H-pyrimidin-2-ones, depending on the substituent on the acetophenone ring and the nature of the solvent (i-PrOH, BuOH, AcOH). The corresponding 5-bromopyrimidin-2-ones were formed on bromination of these compounds. The structures of these compounds were confirmed by IR, UV, and 1H NMR spectroscopy. 相似文献
10.
L. I. Belen'kii T. G. Kim I. A. Suslov N. D. Chuvylkin 《Russian Chemical Bulletin》2005,54(4):853-863
Data on the relative reactivities (substrate selectivity) of five-membered heterocycles in electrophilic substitution reactions
and positional selectivity (α : β ratio) in these reactions were analyzed. Unlike the substrate selectivity (pyrrole ≫ furan
> selenophene > thiophene) determined by the position of heteroatoms in the Periodic Table, the positional selectivity decreases
in the order corresponding to the change in the relative stability of the onium states of the elements (O+ < Se+ ≤ S+ < N+) and reflects the predominant role of heteroatoms in the stabilization of σ complexes formed upon β-substitution. These differences
in the positional selectivity of the parent heterocycles have a substantial effect on the orientation in electrophilic substitution
reactions in their derivatives and the corresponding benzoannelated systems. This interpretation was confirmed by ab initio quantum chemical calculations (RHF/6–31G(d) and MP2/6– 31G(d)//RHF/6–31G(d)) and density functional theory calculations (B3LYP/6–31G(d)).
Quantum chemical calculations were performed by the above-mentioned methods for model N-R-pyrroles (R = Me, Et, Pri, But, CH=CH2, C≡CH, Ph, PhSO2, and 4-O2NC6H4) and their α- and β-protonated σ complexes. The results of these calculations demonstrated that it is the steric factors
and charges on the β-C, α-C, and N atoms and the substituents at the N atom (the kinetic control), as well as the nature of
the electrophile, rather than the difference in the relative stabilities of the onium states of N+ (which depends on the nature of the substituent at the N atom and reflects the role of the heteroatom in stabilization of
σ complexes formed via β-substitution; the thermodynamic control) that are responsible for the type of orientation (α or β) that prevails.
Dedicated to Academician V. I. Minkin on the occasion of his 70th birthday.
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Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 837–846, April, 2005. 相似文献
11.
A wide range of mono-and disubstituted 2,3-dihydroquinazolin-4(1H)-ones were obtained in high yields by condensation of isatoic anhydride,aldehydes with ammonium salts or primary amines in the presence of strontium chloride in aqueous ethanol under reflux. 相似文献
12.
Iraj Mohammadpoor-Baltork Ahmad R. Khosropour Majid Moghadam Shahram Tangestaninejad Valiollah Mirkhani Saeid Baghersad Arsalan Mirjafari 《Comptes Rendus Chimie》2011,14(10):944-952
An efficient and novel synthesis of 2,3-disubstituted 2,3-dihydroquinazolin-4(1H)-ones via one-pot, three-component reaction of isatoic anhydride, primary amines and aromatic aldehydes catalyzed by Bi(NO3)3·5H2O under solvent-free conditions is described. Oxidation of these 2,3-dihydroquinazolin-4(1H)-ones to their quinazolin-4(3H)-ones was also successfully performed in the presence of Bi(NO3)3·5H2O. This new method has the advantages of convenient manipulation, short reaction times, excellent yields, very easy work-up, and the use of commercially available, low cost and relatively non-toxic catalyst. The role of Bi(NO3)3·5H2O was also investigated in these transformations. 相似文献
13.
Wolfgang Stadlbauer Rita Laschober Thomas Kappe 《Monatshefte für Chemie / Chemical Monthly》1991,122(10):853-861
Summary 4-Chloro-3-aryl-coumarins and quinolones2 a–e undergo thermolytic ring closure by reaction with sodium azide in refluxing dimethyl formamide to yield indolo[3,2-c]coumarins and indolo[3,2-c]quinolin-6(5H)-ones6 a–e. In the case of the coumarin2 a the azido coumarin5 can be isolated. The mono- and diazacoumestrol-dimethylethers6 a–c are converted into the coumestrol analogues7 a–c and their diacetyl derivatives8 a–c.
Potentielle nichtsteroidale Östrogene und Antiöstrogene, 4. Mitt.: Organische Azide in der Heterocyclensynthese, Teil 13: Synthese von Aza- und Diazacumöstrolen über Azidzwischenstufen
Zusammenfassung 4-Chlor-3-arylcumarine und-chinolone2 a–e reagieren thermolytisch mit Natriumazid in siedendem Dimethylfomamid unter Ringschluß zu Indolo[3,2-c]cumarinen und Indolo[3,2-c]chinolin-6(5H)-onen6 a–e. Nur aus dem Cumarinderivat2 a kann das zwischenzeitlich gebildete Azidocumarin5 isoliert werden. Die so erhaltenen Mono- und Diazacumöstroldimethylether6 a–c werden in die entsprechenden Cumöstrole7 a–c und ihre Diacetylderivate8 a–c umgewandelt.相似文献
14.
Sonogashira cross-coupling of 3-chloro-6,8-dimethylpyrimido[4,5-c]pyridazine-5,7(6H,8H)-dione with terminal alkynes afforded the corresponding 3-(alkyn-1-yl) derivatives. Oxidative amination of the latter compounds with primary alkylamines was accompanied by heterocyclization to give 6,8-dimethylpyrrolo[3",2":3,4]pyrimido[4,5-c]pyridazine-7,9(6H,8H)-diones. 相似文献
15.
16.
The reactions of 1-amino-2-phenylethynyl-and 2-acylethynyl-1-amino-9,10-anthraquinones with HNO2 in a mixture of dioxane and a mineral acid at 20 °C were studied. Under these conditions, 2-alkynyl-1-amino-9,10-anthraquinones,
irrespective of the structure of the C=CR substituent, are cyclized into 3-substituted 1H-naphtho[2,3-glindazole-6,11-diones. The nature of the acetylenic group in the initial compound and the choice of the mineral
acid determine the structure of the substitutent in position 3 of the product (1,1-dichloroalkyl or acyl) but have no effect
on the regiospecificity of cyclization.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 110–114, January, 1997. 相似文献
17.
Starosotnikov A. M. Kachala V. V. Lobach A. V. Vinogradov V. M. Shevelev S. A. 《Russian Chemical Bulletin》2003,52(8):1782-1790
A method for the synthesis of 1-aryl-3-formyl-4,6-dinitro-1H-indazoles by the reaction of picrylacetaldehyde with aryldiazonium salts followed by intramolecular cyclization of the resulting picrylglyoxal monoarylhydrazones was developed. Various 4,6-dinitro-1-phenyl-1H-indazoles substituted in position 3 were prepared via transformations involving the formyl group of 3-formyl-4,6-dinitro-1-phenyl-1H-indazole. 3-R-4,6-Dinitro-1-phenyl-1H-indazoles (R = CHO, CN, 1,3-dioxolan-2-yl) react regiospecifically with anionic O-, S-, and N-nucleophiles, in particular, with replacement of only the 4-NO2 group. Thus previously unknown 3-R-4-Nu-6-nitro-1-phenyl-1H-indazoles were synthesized (Nu is a nucleophile residue). 相似文献
18.
Substituted benz[g]indole-6,9-diones were synthesized by intramolecular cyclization of 6-alkynyl-5-amino-3-diethylamino-1,-4-naphthoquinones. A method was developed for the preparation of 2-aryl(or alkyl)-4,9-bis(dialkylamino)benzo[h]quinoline-7,10-diones, which involves the addition of a secondary amine to 6-acylethynyl-5-amino-3-diethylamino-1,-4-naphthoquinone followed by cyclization of the resulting adduct.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 412–418, February, 2005. 相似文献
19.
The reactions of sodium bis(2-methoxyethoxy)aluminum hydride with 3-cyano-6-methylpyridine-2(1H)-thione and 3-cyano-6-methyl-2-methylthiopyridine afforded 3-aminomethyl-6-methylpyridine-2(1H)-thione and azomethine of the pyridine series, respectively. The corresponding reaction with 3-cyano-4,6-dimethyl-2-methylthiopyridine gave rise to azomethine, substituted 3-aminomethylpyridine, and substituted dipyridylmethane. 相似文献
20.
G. A. Zhumabaeva S. K. Kotovskaya N. M. Perova V. N. Charushin O. N. Chupakhin 《Russian Chemical Bulletin》2006,55(7):1243-1247
Reactions of 3-fluoro-1-nitrobenzenes with guanidine hydrochloride in THF in the presence of ButOK gave isomeric 5-and 7-fluoro-containing 3-amino-1,2,4-benzotriazines.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1196–1200, July, 2006. 相似文献