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ABSTRACT: The sequential reaction of ketones with arylacetylenes and hydroxylamine in the presence of KOBu(t)/DMSO followed by the treatment of the reaction mixture with H(2)O and KOH leads to Δ(2)-isoxazolines in up to 88% yield.
Organic Letters 12/2012; · 5.86 Impact Factor
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ABSTRACT: A wide variety of β,γ-unsaturated ketones of E configuration have been obtained in good to excellent yields via KO(t)Bu/DMSO promoted α-vinylation of aliphatic, cycloaliphatic, and alkyl aromatic (heteroaromatic) ketones with diverse arylacetylenes.
The Journal of Organic Chemistry 07/2012; 77(16):6880-6. · 4.45 Impact Factor
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ABSTRACT: BODIPYrrole: A general strategy for the design of novel BODIPY fluorophores based on pyrroles with polycondensed aromatic and metallocene substituents has been developed. The strategy involves the acylation of the condensed substituent and treatment of the acylated derivative (as oxime) with acetylene in MOH/DMSO (M=alkali metal) to give pyrroles that were then used for assembly of the BODIPY fluorophores.
Chemistry 02/2011; 17(11):3069-73. · 5.93 Impact Factor
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Annalen der Chemie und Pharmacie 11/2010; 2010(35):6727 - 6730. · 3.10 Impact Factor
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ABSTRACT: Alkylaryl- and alkylheteroarylketones, including those with condensed aromatic moieties, are readily vinylated with arylacetylenes (KOH/DMSO, 100 degrees C, 1 h) to give regio- and stereoselectively the (E)-beta-gamma-ethylenic ketones ((E)-3-buten-1-ones) in 61-84% yields and with approximately 100% stereoselectivity. This vinylation represents a new C(sp(3))-C(sp(2)) bond-forming reaction of high synthetic potential.
Chemistry 07/2010; 16(28):8516-21. · 5.93 Impact Factor
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Boris A. Trofimov,
Elena Yu. Schmidt,
Igor A. Ushakov,
Albina I. Mikhaleva, Nadezhda V. Zorina,
Nadezhda I. Protsuk,
Elena Yu. Senotrusova,
Elena V. Skital'tseva,
Olga N. Kazheva,
Grigorii G. Alexandrov,
Oleg A. Dyachenko
Annalen der Chemie und Pharmacie 09/2009; 2009(30):5142 - 5145. · 3.10 Impact Factor
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Boris A Trofimov,
Elena Yu Schmidt,
Albina I Mikhaleva,
Cristina Pozo-Gonzalo,
Jose A Pomposo,
Maitane Salsamendi,
Nadezhda I Protzuk, Nadezhda V Zorina,
Andrey V Afonin,
Alexander V Vashchenko,
Ekaterina P Levanova,
Galina G Levkovskaya
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ABSTRACT: Bridging pyrrole and selenophene chemistries: Molecular assemblies have been developed that allow scrutiny of the electronic communication between pyrrole and selenophene nuclei. Divergent syntheses of 2-(selenophen-2-yl)pyrroles and their N-vinyl derivatives from available 2-acylselenophenes and acetylenes in a one-pot procedure have been devised (see scheme), which provide access to these exotic heterocyclic ensembles.The divergent syntheses of 2-(selenophen-2-yl)pyrroles and their N-vinyl derivatives from available 2-acylselenophenes and acetylenes in a one-pot procedure make these exotic heterocyclic ensembles accessible. Now we face a potentially vast area for exploration with a great diversity of far-reaching consequences including conducting electrochromic polymers with repeating of pyrrole and selenophene units (emerging rivalry for polypyrroles and polyselenophenes), the synthesis of functionalized pyrrole-selenophene assembles for advanced materials, biochemistry and medicine, exciting models for theory of polymer conductivity.
Chemistry 06/2009; 15(26):6435-45. · 5.93 Impact Factor
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Elena Yu Schmidt,
Boris A Trofimov,
Al'bina I Mikhaleva, Nadezhda V Zorina,
Nadezhda I Protzuk,
Konstantin B Petrushenko,
Igor A Ushakov,
Marina Yu Dvorko,
Rachel Méallet-Renault,
Gilles Clavier,
Thanh Truc Vu,
Ha Thanh Thao Tran,
Robert B Pansu
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ABSTRACT: 2-(Benzo[b]thiophene-3-yl)-1-vinylpyrrole has been synthesized directly from 3-acetylbenzo[b]thiophene oxime and acetylene (flow system, KOH-DMSO, 120 degrees C, 5 h) in 68% yield. Devinylation of the synthesized pyrrole (Hg(OAc)(2), NaBH(4), 50 degrees C) led to the corresponding 2-(benzo[b]thiophene-3-yl)pyrrole in 63% yield. Trifluoroacetylation of both the pyrroles with trifluoroacetic anhydride (80 degrees C, 1 h) gave the corresponding 5-trifluoroacetyl pyrroles in 97% and 76% yields, respectively. 2-(Benzo[b]thiophene-3-yl)pyrrole was reacted subsequently with mesityl aldehyde, 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ), and BF(3)OEt(2) to afford 4,4-difluoro-3,5-di(benzo[b]thiophene-3-yl)-8-mesityl-4-bora-3a,4a-diaza-s-indacene, a representative of the novel BODIPY fluorophore family (BODIPY = 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene), in 34% overall yield. The synthesized pyrroles exhibit promising optical properties (absorption and emission spectra, nonlinear optical (NLO) features), superior to existing analogues. The BODIPY fluorophore displays an intense red-shifted fluorescence emission in CH(2)Cl(2) (625 nm, 0.84 fluorescence quantum yield) that is fully preserved in the solid state.
Chemistry 05/2009; 15(23):5823-30. · 5.93 Impact Factor
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ABSTRACT: The N-H...X (X = N,O,S) intramolecular hydrogen bond in the series of 2(2'-heteroaryl)pyrroles and their trifluoroacetyl derivatives is examined by the (1)H, (13)C, (15)N spectroscopy and density functional theory (DFT) calculations. The influence of the hydrogen bond on coupling and shielding constants is considered. It is shown that the N-H...N intramolecular hydrogen bond causes a larger increase in the absolute size of the (1)J(N,H) coupling constant and a larger deshielding of the bridge proton than the N-H...O hydrogen bond. The effect of the N-H...S interaction on the (1)J(N,H) coupling constant and the shielding of the bridge proton is small. The NMR parameter changes in the series of the 2(2'-heteroaryl)pyrroles due to N-H...X hydrogen bond and the series of the 1-vinyl-2-(2'-heteroaryl)-pyrroles due to C-H...X hydrogen bond have the same order. The proximity of the nitrogen, oxygen or sulfur lone pair to the F...H hydrogen bridge quenches the trans-hydrogen bond spin-spin couplings (1h)J(F,H-1) and (2h)J(F,N).
Magnetic Resonance in Chemistry 06/2008; 46(5):441-7. · 1.44 Impact Factor
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ABSTRACT: A series of 2,2′-dipyrrole monomers separated by aza-spacers (N,N′-bis-(1H-pyrrol-2-ylmethylene)-benzene-1,4-diamine; N4,N4′-bis-(1H-pyrrol-2-ylmethylene)-biphenyl-4,4′-diamine; N,N′-bis-[1-(1H-pyrrol-2-yl)-ethylidene]-hydrazine; and 4,4′-bis[(1H-pyrrol-2-yl)-diazenyl]biphenyl) have been synthesised using modified Schiff and azo-coupling reactions. The new 2,2′-dipyrroles linked with conjugated aza-spacers have been evaluated as precursors of narrow band gap conducting polymers. Electrochemically synthesized poly(N,N′-bis-[1-(1H-pyrrol-2-yl)-ethylidene]-hydrazine) displays a narrow band gap of just 0.7 eV, making it a suitable candidate for optoelectronic applications.
Synthetic Metals 157(1):60-65. · 1.83 Impact Factor
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Alexander M. Vasil'tsov,
Elena Yu. Schmidt,
Al'bina I. Mikhaleva, Nadezhda V. Zorina,
Alexey B. Zaitsev,
Olga V. Petrova,
Leonid B. Krivdin,
Konstantin B. Petrushenko,
Igor' A. Ushakov,
Cristina Pozo-Gonzalo,
José A. Pomposo,
Hans-Jürgen Grande
Tetrahedron. 61(32):7756-7762.
