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1.
Sobha P. Gorugantula 《Tetrahedron》2010,66(10):1800-4757
Palladium-catalyzed, carbon monoxide-mediated reductive N-heterocyclization of nitro-heteroaromatic compounds having an alkene adjacent to the nitro-group affords bicyclic pyrrolo-fused heteroaromatic molecules. This type of reaction was used to prepare the fused bicyclo[3.3.0] ring-system: thieno[3,2-b]pyrrole, thieno[2,3-b]pyrrole, furo[2,3-b]pyrrole, pyrrolo[3,2-d]thiazole, and pyrrolo[2,3-d]imidazole and the bicyclo[4.3.0] ring-systems: pyrrolo[3,2-b]pyridine, pyrrolo[2,3-b]pyridine, pyrrolo[3,2-c]pyridine, pyrrolo[2,3-c]pyridine, pyrrolo[3,2-c]pyridazine, and pyrrolo[3,2-d]pyrimidine in 32-94% yield. 相似文献
2.
Vegar Stockmann 《Tetrahedron》2008,64(49):11180-11184
Three novel pyrido-fused tris-heterocycles have been prepared based on a Suzuki coupling and subsequent cyclisation approach. Pyrido[4,3-e]pyrrolo[2,3-c]pyridazine (3b, 77%) and pyrido[4,3-e]furano[2,3-c]pyridazine (5b, 76%) were obtained by intramolecular diazocoupling. Successful diazocoupling of furan (5b) is thus reported for the first time by NOBF4 generation of the diazonium intermediate. N-TIPS-pyrido[3,4-b]pyrrolo[3,2-d]pyrrole (TIPS-4b) was synthesised by thermal cyclisation of pyridyl nitrene in considerably higher yield (71%) than previously experienced from similar cyclisations, due to TIPS-activation. 相似文献
3.
Katarzyna Ostrowska Katarzyna SzymoniakMagdalena Szczurek Krzysztof Jamro?y Maria R?pa?a-Kozik 《Tetrahedron》2011,67(29):5219-5227
The regioselective syntheses of substituted pyrrolo[2,3-b]quinoxaline, pyrido[2,3-b]pyrrolo[2,3-e]pyrazine, pyrido[2,3-b]pyrrolo[3,2-e]pyrazine and pyrido[3,4-b]pyrrolo[3,2-e]pyrazine are reported. Differential reactivity between two amino groups in ortho-diaminopyridine can be exploited to obtain new regio-defined unsymmetrical pyridopyrrolopyrazine derivatives. Weak electron-donating methyl or moderately electron-withdrawing carboxylic groups attached to the aromatic ortho-diamines reduce the regioselectivity of obtaining unsymmetrical substituted pyrrolo[2,3-b]quinoxaline. The fluorescence properties of the resultant 1-alkyl pyridopyrrolopyrazine and substituted pyrrolo[2,3-b]quinoxaline derivatives are presented. 相似文献
4.
Magdi E.A. Zaki A. Paula Bettencourt Francisco M. Fernandes M. Fernanda Proença 《Tetrahedron》2012,68(24):4628-4634
Substituted 4-(2,5-dihydro-1H-pyrrol-3-yl)-1H-imidazoles were prepared from 5-amino-1-aryl-4-cyanoformimidoylimidazoles and cyanoacetamide, under mild experimental conditions. The pyrrolyl-imidazoles were cyclized to the corresponding 7,8-dihydroimidazo[4,5-b]pyrrolo[3,4-d]pyridines by reflux in ethanol, with catalysis by DBU. The same pyrrolyl-imidazoles were reacted with orthoesters, at room temperature and in the presence of sulfuric acid, to generate 3,7-dihydro-8H-imidazo[4,5-d]pyrrolo[3,2-f]diazepines in very good yield. Electrochemical studies of the imidazo[4,5-d]pyrrolo[3,2-f][1,3] diazepine derivatives were carried out. The reduction potential of 7-ethyl-3-(4-methoxyphenyl)-8-oxo-7,8-dihydro-3H-imidazo[4,5-d]pyrrolo[3,2-f][1,3] diazepine-9-carbonitrile was in the adequate range for presenting bioreduction properties. 相似文献
5.
E. Aiello G. Dattolo G. Cirrincione S. Plescia G. Daidone 《Journal of heterocyclic chemistry》1978,15(4):537-539
A new synthesis of pyrrolo[3,2-b] pyridine starting with pyrrole ring is described. The procedure allows the synthesis of 4-azaindoles bearing a sensitive group at C-7. The nitration of 4b with nitric acid and acetic anhydride at ?15° gave 5 . The hydrogenation of 5 led to simultaneous reduction of N-hydroxy and nitro groups and to hydrogenolysis of the isoxazole nucleus, affording an appropriate chain of atoms to building up the pyrrolo[3,2-b] pyridine ring. 相似文献
6.
A four-step synthesis of 5-carboxamidopyrrolo[3,2-b]pyridine ( 3 ) from pyrrolo[3,2-b]pyridine ( 4 ) is described (45% overall yield). The one-step conversion of the N-oxide 6 of the pyrrolo[3,2-b]pyridine 5 leads to the 5-cyanopyrrolo[3,2-b]pyridine 7. The cyano group is hydrolyzed to afford the title compound 3 , which is the 4-aza analog of the indole backbone in 5-carboxamidotryptamine, a potent agonist of the neurotransmitter, serotonin. 相似文献
7.
The synthesis and selected reactions of the versatile heterocycle 2-amino-3-cyanomethylsulfonyl-4,5-dimethylfuran is reported. In particular, cyclization reaction of the aminofuran yielded a number of novel furo[3,2-b]thiazine 1,1-dioxides. Additionally, a novel tetracyclic system, namely a pyrrolo[2′,3′:5,6]-[1,4]thiazino[3,2-b]quinoline 4,4-dioxide, is prepared via an intramolecular triple-cyclization in which the furan ring is opened and reclosed as a pyrrole. 相似文献
8.
I. V. Voznyi M. S. Novikov A. F. Khlebnikov R. R. Kostikov 《Russian Journal of Organic Chemistry》2006,42(5):689-695
Reactions of N-(5-R-furan-2-ylmethylidene)anilines with difluorocarbene proceeds through intermediate azomethine ylides suffering 1,5-π-cyclization to yield 6,6-difluorocyclopropa[b]furo[2,3-c]pyrrole and/or 4,4,6,6-tetrafluorocyclopropa[b]furo[2,3-c]pyrrole. The heating of these compounds without solvent resulted in high yields of 2,5-disubstituted 7-fluoro-4,5-dihydrofuro[3,2-c]pyridin-4(5H)-ones. 相似文献
9.
Pavel A. Sakharov Nikolai V. Rostovskii Alexander F. Khlebnikov Mikhail S. Novikov 《Molecules (Basel, Switzerland)》2022,27(17)
A method for the [2+3] pyrroline annulation to the six-membered non-aromatic enols using 3-aryl-2H-azirines as annulation agents is developed in the current study. The reaction proceeds as a formal (3+2) cycloaddition via the N1-C2 azirine bond cleavage and is catalyzed by both Cu(II) and Cu(I) compounds. The new annulation method can be applied to prepare pyrrolo[3,2-c]quinoline, chromeno[3,4-b]pyrrole, and naphtho[1,8-ef]indole derivatives in good to excellent yields from enols of the quinolin-2-one, 2H-chromen-2-one, and 1H-phenalen-1-one series. 相似文献
10.
A series of 4-substituted 3-(indole-3-yl)maleimides has been synthesized. Upon the action of CH3SO3H in TFA, the 3-(indole-3-yl)-4-(arylalkylamino)-maleimides undergo cyclization to give 12b,13-dihydro-4bH-indolo[3,2-d]pyrrolo[3,4-b][1]benzazepine-5,7(6H,8H)-dione derivatives. 相似文献
11.
I. B. Zavarzin N. G. Smirnova V. N. Yarovenko M. M. Krayushkin 《Russian Journal of Organic Chemistry》2007,43(5):753-757
By oxidation of monothiooxamides with K3[Fe(CN)6]pyrrolo[3,2-d][1,3]thiazoledicarboxylic acid was obtained used further in the synthesis of 2,4,5-trimethyl-4H-pyrrolo[3,2-d][1,3]thiazole. 相似文献
12.
Cosme G. Francisco 《Tetrahedron letters》2007,48(36):6384-6388
The preparation of 2-amino-C-glycosides of the hexahydro-2H-furo[3,2-b]pyrrole and octahydropyrano[3,2-b]pyrrole systems is described. A tandem 1,5-hydrogen atom transfer-radical oxidation-nucleophilic cyclisation mechanism is proposed for the intramolecular hydrogen atom transfer reaction promoted by carbamoyl and phosphoramidyl radicals employing hipervalent iodine oxidants. 相似文献
13.
Jean-Marie Webert Denise Cagniant Paul Cagniant Gilbert Kirsch Jean-Victor Weber 《Journal of heterocyclic chemistry》1983,20(1):61-64
The influence of annelaction and of the heteroatom upon the reactity of some haterocyclic analogus of phenanthrene with a pyrrole nucleos was tested toward acetylation and lithiation. If methy-l[1]benzofuro-[3,2-b]pyrrole was acetylated only in the 2-position, the sulfer and selenious analogues with [3,2-b] and [2,3-b] annelarion were acetylated in the -2 and -3 position. No reaction at all or only with poor yield (in the oxygenated series) was observed with butyllithium except on the case of l-methyl[1]benzoselenono[2,3-b]pyrrole, where the opening of the selenophene nucleos gives, after carbonation and action of diazomethane, l-methyl-2-methoxycarbony 1-3-(o-methylselenophenyl) pyrrole. 相似文献
14.
The first derivatives of the pyrrolo[3,2-c]pyridazine ring system, ethyl pyrrolo[3,2-c]pyridazine-6-carboxylate 2-oxide (5) and ethyl 3-chloro-6-methylpyrrolo[3,2-c]pyridazine-7-glyoxalate 1-oxide ( 12 ), were obtained in good yields from the cyclization of 4-ethoxymethyl-eneamino-3-methylpyridazine 1-oxide (3) and 3-chloro-5-(α-ethoxyethylideneamino)-6-methylpyridazine 1-oxide (14, R ? Cl, R1 ? OMe), respectively, with diethyl oxalate and potassium ethoxide in ether. 相似文献
15.
Treatment of the zerovalent platinum complex [Pt(PEt3)4] with 3,6-dimethylthieno[3,2-b]thiophene leads to a six-membered, approximately planar thiaplatinacycle, which has been characterised spectroscopically and by a single crystal X-ray determination. The reaction of [Pt(PEt3)4] with 2,2′-bithiophene and 1-methyl-2-(2-thienyl)pyrrole produced two types of products, thiaplatinacycles resulting from CS insertion and platinum(II) hydrides arising from CH insertion. These complexes were characterised spectroscopically. 相似文献
16.
Dr. Mariusz Tasior Dr. Małgorzata Czichy Prof. Mieczysław Łapkowski Prof. Daniel T. Gryko 《化学:亚洲杂志》2018,13(4):449-456
Dibenzothienopyrrolo[3,2‐b]pyrrole and the corresponding bis(S,S‐dioxide) were synthesized by using a concise synthetic strategy. Despite the presence of six fused aromatic rings, π‐expanded pyrrolo[3,2‐b]pyrroles of this type absorb and emit at relatively short wavelengths, which reflects inefficient π conjugation due to the angular arrangement of the aromatic rings. They exhibit interesting and complex electrochemical behavior, which highlights their potential in organic electronics. Both heteroacenes undergo two‐stage oxidation while retaining the independence of each 1‐phenyl‐1H‐[1]benzothieno[3,2‐b]pyrrole, which was proved by in situ electron spin resonance measurements. Interestingly, electrochemically generated dicationdiradicals are not only distributed over the pyrrolo[3,2‐b]pyrrole scaffold, but also over the phenyl substituents located on nitrogen atoms. 相似文献
17.
Sudipta Ponra Mukut Gohain Rajashekar Donka Johannes H. van Tonder Barend C.B. Bezuidenhoudt 《Tetrahedron letters》2018,59(30):2909-2912
A series of polysubstituted pyrrolo[3,2-d]pyrimidinedione derivatives have been synthesized in excellent yields. This prominent scaffold is obtained via an Al(OTf)3-catalyzed tandem addition-annulation sequence between propargylic alcohols and aminopyrimidines. The process is simple, facile, inexpensive, and provides a diverse range of substituted pyrrolo [3,2-d]pyrimidinedione derivatives with short reaction times from readily obtainable starting materials. 相似文献
18.
N. S. Masterova L. M. Alekseeva A. S. Shashkov V. A. Tafeenko S. Yu. Ryabova V. G. Granik 《Russian Chemical Bulletin》2008,57(8):1765-1772
Alkylation of 11-benzyl-3,11-dihydro-4H-pyrimido[5′,4′:5,6]pyrido[3,2-b]indol-4-one with methyl iodide and methyl bromoacetate in DMF gave 3-alkylpyrimidopyridoindolones as the corresponding salts. The reaction in acetone in the presence of K2CO3 yielded 3,6-disubstitution products. Alkylation with DMF dimethyl acetal gave a mixture of the 3- and 6-alkylpyrimidopyridoindol-4-one bases. The structure of 4-oxo-4,6-dihydro-3H-pyrimido-[5′,4′:5,6]pyrido[3,2-b]indol-11-ium chloride (3b) was proved by X-ray diffraction analysis. 相似文献
19.
Olga V. Vinogradova 《Tetrahedron letters》2009,50(46):6358-6941
Cleavage of ortho-(dodeca-1,3-diynyl)triazenes in HCl or HBr medium and subsequent cyclization of the resulting diazonium salts is investigated. In the absence of a strong electron-withdrawing substituent, the reaction affords 3-alkynyl-4-bromo(chloro)cinnolines as the only product. A methoxycarbonyl group promotes hydrolysis of 4-halocinnolines which results in the formation of by-products: furo[3,2-c]cinnoline and cinnolinone. Substitution of bromine in 3-(alk-1-ynyl)-4-bromocinnolines is achieved with methylamine, Na2S and ethynylbenzene affording pyrrolo[3,2-c]cinnoline, thieno[3,2-c]cinnoline and 3,4-diethynylcinnoline, respectively. 相似文献
20.
《Mendeleev Communications》2022,32(4):523-526
Five new dyes with D–π–A structure bearing 5-(methylene)-rhodanine-3-acetic acid as an acceptor-anchoring part and thieno[3,2-b]indole or benzo[g]thieno[3,2-b]indole as an electron-donating part were synthesized and applied as photosensitizers for dye-sensitized solar cells (DSSCs). In addition, thermal stability, optical and electrochemical properties of these dyes were investigated. The highest PCE value of 1.09% (Jsc = 3.01 mA cm–2, Voc = 0.53 V, FF = 0.69) was achieved for DSSC based on benzo[g]thieno[3,2-b]indole dye under AM 1.5G irradiation. 相似文献