Electrophilic addition of phenols to 1-vinyl-4,5,6,7-tetrahydroindole

Both uncatalyzed and acid-catalyzed (CH₃COOH) addition of phenols to 1-vinyl-4,5,6,7-tetrahydroindole gave 1-(1-aroxyethyl)-4,5,6,7-tetrahydroindoles. With increasing acidity of the phenol and in the presence of CF₃COOH the yield of adducts was lowered because of the oligomerization of 1-vinyl-4,5,6,7-tetrahydroindole.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 604–606, May, 1989.     

Transformations of 2-trifluoroacetyl-4,5,6,7-tetrahydro-1H-pyrrolo[3,2-c]pyridines by the action of ethyl propynoate. A novel synthesis of 2-trifluoroacetyl-4,7,8,9-tetrahydro-1H-pyrrolo[2,3-d]azocines

2-Trifluoroacetyl-4,5,6,7-tetrahydro-1H-pyrrolo[3,2-c]pyridines reacted with ethyl propynoate in acetonitrile and methanol to give ethyl 2-trifluoroaceyl-4,7,8,9-tetrahydro-1H-pyrrolo[2,3-d]azocine-5-carboxylates. The reactions of 2-trifluoroacetyl-1-vinyl-4,5,6,7-tetrahydro-1H-pyrrolo[3,2-c]pyridines with ethyl propynoate in alcohols were accompanied by cleavage of the tetrahydropyridine fragment with formation of alkyl 3-{benzyl[2-(3-alkoxy-5-trifluoroacetyl-1-vinyl-1H-pyrrol-2-yl)ethyl]amino}acrylates.     

Developing qualitative extraction profiles of coffee aromas utilizing polymeric ionic liquid sorbent coatings in headspace solid-phase microextraction gas chromatography-mass spectrometry

Two solid-phase microextraction (SPME) sorbent coatings based on polymeric ionic liquids (PILs) have been utilized for the analysis of complex coffee aroma samples. The PIL-based SPME coatings examined, namely, poly(1-(4-vinylbenzyl)-3-hexadecylimidazolium bis[(trifluoromethyl)sulfonyl]imide) [poly(VBHDIm⁺ NTf₂⁻)], with ∼14-μm thickness, and poly(1-vinyl-3-hexylimidazolium chloride) [poly(ViHIm⁺ Cl⁻)], with ∼8-μm thickness, were employed for the headspace determination of up to 49 analytes from four different coffee beans: two French roast coffees of different brands, Sumatra coffee, and decaffeinated Sumatra coffee. The analysis was conducted using gas chromatography coupled to mass spectrometry. For comparative purposes, the commercial polyacrylate (PA, 85-μm film thickness) SPME coating was utilized under the same extraction conditions. The three SPME coatings tested behaved quite differently as a function of the families of compounds extracted. Thus, the poly(VBHDIm⁺ NTf₂⁻) coating was extremely selective for aldehydes while also exhibiting good extraction efficiencies for acids. The poly-(ViHIm⁺ Cl⁻) coating exhibited superior performance for aromatic alcohols, and the PA coating worked better for heterocyclic aromatics. Both PIL-based SPME sorbent coatings demonstrated exceptional selectivity and extraction efficiency when dealing with complex coffee aromas in spite of their small film thicknesses.     

PMR spectral study of the structure of 1-vinyl-2-(2-furyl)- and 2-(2-thienyl)pyrroles

Conclusions PMR spectral data indicate that the heterocycles in 1-vinyl-2-(2-fury1- and 1-vinyl-2-(2-thienyl) pyrroles lie in a single plane with syn arrangement of the heteroatoms and trans orientation of the vinyl group relative to the non-pyrrole heterocycle. Molecular coplanarity is lost in 3-alky1-1-vinyl-2-(2-furyl)- and 3-alkyl-1-vinyl-2-(2-thienyl) pyrroles.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 184–186, January.     

Chemical release control: Carbamates of 3-vinylphenyl and 2-methacryloyloxyethyl isocyanates and perfume and herbicide alcohols

Polymerizable carbamates were synthesized from 3-vinylphenyl and 2-methacryloyloxyethyl isocyanates and perfume and herbicide alcohols, such as 2-phenethyl alcohol, citronellol, geraniol, 1-menthol, borneol, and 2-(2,4-dichlorophenoxy)- and 2-(2,4,5-trichlorophenoxy)ethyl alcohols. Copolymerization of these carbamate monomers and N-vinyl-2-pyrrolidone with AIBN in dioxane gave respective copolymers. Hydrolyses of both monomers and copolymers, however, required severe acid conditions, although different chemical structures gave different hydrolytic behaviors.     

Synthesis and modification of 1-vinylpyrrole-2-carbaldehyde polymers

1-Vinylpyrrole-2-carbaldehydes, viz., 5-phenyl-1-vinylpyrrole-2-carbaldehyde, 5-(2-thienyl)-1-vinylpyrrole-2-carbaldehyde, 1-vinyl-4,5,6,7-tetrahydroindole-2-carbaldehyde, and 1-vinyl-4,5-dihydrobenz[g]indole-2-carbaldehyde, are polymerized in the presence of 2,2-azobisisobutyronitrile to form soluble paramagnetic oligomers. A possibility of oligomer modification through the aldehyde moiety with amines and thiols was shown. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2134–2137, November, 2007.     

Reaction of 1-(alk-1-ynyl)-1-halocyclopropanes with alcohols and phenol in KOH/DMSO as a method for the synthesis of 2-alkoxy-1-alkynyl- and 1-alkynyl-2-phenoxycyclopropanes

The reaction of 1-(alk-1-ynyl)-1-halocyclopropanes with alcohols or phenol in KOH/DMSO at 80–100 °C leads to the corresponding alkynylalkoxy- and alkynylphenoxycyclopropanes in up to 80% yield. These reactions proceed through the intermediate formation of conjugated alkynylcyclopropenes capable of the in situ addition of alcohols at the double bond of the cyclopropene fragment. Regio- and stereoselectivity of the process is defined by the nature of substituents in the starting cyclopropanes and the structure of alcohols used.     

Nucleophilic addition of 2-hydroxyquinoxaline to acetylenes

Vinylation of 2-hydroxyquinoxaline affords either 2-vinyloxyquinoxaline or 1-vinyl-2-quinoxalone depending on the reaction conditions. The reactions of 2-hydroxyquinoxaline with 3-phenylprop-2-ynonitrile or 4-hydroxyalk-2-ynonitriles yield 3-phenyl-3-(quinoxalyl-2-oxy)prop-2-enonitrile or 4-hydroxy-3-(quinoxalyl-2-oxy)alk-2-enonitriles, respectively. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 738–741, April, 2000.     

Polarographic reduction of 1-substituted 1,2,4-triazoles

The polarographic reduction of 1-substituted 1,2,4-triazoles in dimethylformamide (DMF) and acetonitrile was studied. 1-Methyl-, 1-ethyl-, and 1,2,4-triazoles are not reduced on a mercury electrode over the range of potentials accessible for polarography. 1-Phenyl-1,2,4-triazole and 1-vinyl-1,2,4-triazole are reduced in acetonitrile via a one-electron mechanism at high negative potentials. The reduction of 1-vinyl-1,2,4-triazole is accompanied by polymerization of the electrolysis products. A possible mechanism for the electrochemical reduction is discussed. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 408–410, March, 1980.     

Synthesis of pyrrolidine and tetrahydroazonine derivatives from <Emphasis Type="Italic">N</Emphasis>-[bis(ethoxycarbonyl)methyl]tetrahydropyridinium bromide and methyl acetylenedicarboxylate

The reaction of N-methyl-N-(diethoxycarbonyl)methyltetrahydropyridinium bromide with dimethyl acetylenedicarboxylate in the presence of triethylamine at room temperature afforded 1,2-dimethyl 1-ethyl 2-[(3-vinyl-1-methyl-3-phenyl-2-ethoxycarbonyl)pyrrolidin-2-yl]-ethene-1,1,2-tricarboxylate in 25% yield. Its structure was proved by XRD analysis. At cooling to −20°C the pyrrolidine yield signifi cantly decreased and 3,4-dimethyl 2,2-diethyl 1-methyl-7-phenyl-1,5,8,9-tetrahydro-2H-azonine-2,2,3,4-tetratcarboxylate was obtained in 31% yield.     

Asymmetric Reduction of Acetophenones with NaBH4 in the Presence of Mono-6-(1-methyl-3-imidazolium)-6-deoxy-β-cyclodextrin Tosylate

The asymmetric reduction of acetophenone and its derivatives was achieved with sodium borohydride utilizing a novel chiral ionic liquid of β-cylclodextrin (CD), mono-6-(1-methyl-3-imidazolium)-6-deoxy-β-cyclodextrin tosylate (MIM-β-CDOTs). It was found that this chiral β-CD-based ionic liquid could provide higher enantioselectivity for the product alcohols. Moreover, the enantioselectivity of the product alcohols was highly dependent on the structure of prochiral ketones, structure of CD and reduction temperature. An erratum to this article can be found at     

Reaction of 3-Aryl-1-(2-methyloxiran-2-yl)prop-2-en-1-ones with Tosylhydrazine

It was established that the reaction of 3-aryl-1-(2-methyloxiran-2-yl)prop-2-en-1-ones with tosylhydrazine leads to 3-[(E)-2-arylvinyl]-4-methyl-1-tosyl-1H-pyrazoles and 3-aryl-1-(2-methyloxiran-2-yl)-3-tosylpropan-1-ones. The latter are formed as a result of rearrangement of the intermediate hydrazino alcohols and/or addition of p-toluenesulfinic acid during reductive degradation of the tosylhydrazine. It was shown that the reaction of 3-aryl-1-(2-methyloxiran-2-yl)-3-tosylpropan-1-ones with an excess of tosylhydrazine leads to 3-(2-aryl-2-tosylethyl)-4-methyl-1-tosyl-1H-pyrazoles. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1481–1489, October, 2005.     

Pyrroles from ketoximes and acetylene. 44. Methyl aryl ketoximes with reactive substituents

The Trofimov reaction was extended to methyl aryl ketoximes with substituents in the benzene ring that are unstable with respect to the action of a strongly basic medium. The corresponding pyrroles and their 1-vinyl derivatives were obtained. 4-Nitroacetophenone oxime, from which only 2-phenyl- and 1-vinyl-2-phenylpyrrole were obtained, and 4-bromoacetophenone oxime, the reaction of which leads to the formation of 1-vinyl-2-(4-vinyloxyphenyl)pyrrole in addition to the principal 2-(4-bromophenyl)pyrrole, constituted exceptions.For communication 43, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 187–191, February, 1991.     

Photophysical characterization of mixed micelles of n-butanol/SDS and n-hexanol/SDS. A study at low alcohol concentrations

 The effect of the addition of n-butanol (BuOH) and n-hexanol (HexOH) on the micellization of sodium dodecylsulfate (SDS) has been investigated using fluorescence quenching methods. The binding constants were calculated using an expression which relates the total concentration of alcohols and the micelle concentration. The values of K were 4.67 and 17.6 M^-1 for BuOH/SDS and HexOH/SDS, similar to values obtained by other methods. The cmc of SDS decreases on addition of alcohols and goes through a minimum for the BuOH/SDS system. Micellar aggregation numbers (N) were determined from linear plots of Ln (I ⁰/I) against [Quencher] at low alcohol concentrations. For 15 mM SDS, in the presence of BuOH the N values decrease on addition of alcohol up to 0.2 M. For HexOH, N can be assumed to be constant up to 4.8 mM, after which N decreases. The polarity of the micellar core containing alcohol was evaluated from the I ₁/I ₃ ratio of monomeric pyrene. The effect of addition of the alcohol causes a decrease in the I ₁/I ₃, which corresponds to a decrease in the polarity of the pyrene solubilization site. Received: 28 October 1996 Accepted: 10 January 1997     

Effect of denaturants on the stability of light-harvesting complex

 The effect of denaturants such as urea and normal alcohols on the formation of light-harvesting (LH) polypeptides/bacteriochlorophyll a (BChla) complex (LH1 complex) in n-octyl-β-D-glucopyranoside (OG) micelle was examined to provide an insight into stability of the complex. The stabilities of the LH1 complex in OG micelle and of the complex in the chromatophore of photosynthetic bacteria were compared by addition of denaturants. The extent of stability of these complexes was monitored by the change in absorbance of Qy band of BChla in these complexes, resulting generally in the blue-shifting of the Qy band from near 870 nm to about 777 nm upon addition of these denaturants. Urea and guanidium hydrochloride (Gnd) showed a relatively weak denaturing effect. Normal alcohols showed stronger denaturing effect, depending on the hydrophobicity of the alcohols. These results imply that the stability of LH1 complex in OG micelle can be largely attributed to the hydrophobic interactions in the complex as well as that of the complex in the chromatophore of photosynthetic bacteria. Received: 23 May 1997 Accepted: 13 September 1997     

Investigations on reactions of cyclene <Emphasis Type="Italic">α</Emphasis>-oxides

The influence of the reaction conditions on the order of addition of alcohols and α-chloro ethers in an acid medium to dioxides of 1-vinyl-3-cyclohexene is described on the basis of a determination of the percentage content of the ratio of the isomers by IR spectroscopy. It has been established that under mild conditions the addition takes place selectively with the predominant opening of the oxide ring attached to the six-membered carbon ring. More severe conditions (higher temperature, smaller amount of solvent) favor the formation of isomers with an opened oxide ring on the ethylene grouping.     

peri-Naphthylenediamines

Tertiary alcohols containing the 4,5-bis(dimethylamino)-1-naphthyl group were synthesized. The carbocations that formed from α-methyl-containing alcohols in an acidic medium underwent smooth El elimination to give the corresponding unsaturated derivatives of the “proton sponge” in good yields. At the same time, the carbocation generated from 4-(α-hydroxybenzhydryl)-1,8-bis(dimethylamino)naphthalene was converted into a benzo-[a]fluorene derivative as a result of a complex reaction which has been previously unknown in the chemistry of “proton sponges.” The structure of the latter derivative was established by X-ray diffraction analysis. For Part 26, see Ref. 1; this paper simultaneously presents Part 5 of the series “Resonance-stabilized α-naphthylmethyl carbocations and derived spiro compounds;” for Part 4, see Ref. 2. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1103–1108, June, 2000.     

Silver recovery with complexing sorbents based on 1-vinyl-1,2,4-triazole

The sorption activity of copolymers based on 1-vinyl-1,2,4-triazole toward silver ions was studied in relation to the copolymer structure and to the kind and concentration of acids. The copolymers were prepared by radical copolymerization of 1-vinyl-1,2,4-triazole with 1,1,3-trihydrotetrafluoropropyl methacrylate and divinylbenzene, with 1,1,3-trihydrotetrafluoropropyl methacrylate, methyl methacrylate, and N,N′-methylenebisacrylamide, with diethylene glycol divinyl ether, and with divinyl sulfide. The copolymers exhibit high sorption activity. They efficiently recover silver cations from acid solutions and behave as anion exchangers.     

Syntheses of copolymers containing pendant cyclic iminoethers and crosslinking reactions of these copolymers with dithiols and dicarboxylic acids

Copolymers containing pendant cyclic iminoethers were prepared by radical copolymerizations of 2-vinyl-2-oxazoline (VOZO), 5-methyl-2-vinyl-2-oxazoline (MVOZO), 4,4-dimethyl-2-vinyl-2-oxazoline (DMVOZO), 4,4-dimethyl-2-vinyl-5,6-dihydro-4H-1,3-oxazine (DMVOZI), and 4,4,6-trimethyl-2-vinyl-5,6-dihydro-4H-1,3-oxazine (TMVOZI) with styrene, methyl methacrylate (MMA), and ethyl acrylate (EA) using AIBN as an initiator. In addition, the monomer reactivity ratios of VOZO, MVOZO, DMVOZO, and DMVOZI with styrene and MMA were determined. The crosslinking reactions of these copolymers with polyfunctional thiols such as 6-(N,N-dibutyl)amino-1,3,5-triazine-2,4-dithiol (DBDT), 4,4′-oxydi(benzenedithiol) (OBDT), and pentaerythritol tetrathioglycolate (PETT), and dicarboxylic acids such as succinic acid, adipic acid, and sebacic acid were carried out at several reaction temperatures. From these results, it was found that the order of reactivity of pendant cyclic iminoethers to the thiols was VOZO > DMVOZO ≥ DMVOZI > MVOZO > TMVOZI, and that of the cyclic iminoethers to the carboxylic acids was VOZO > MVOZO ≥ DMVOZI > TMVOZI ≥ DMVOZO. Furthermore, the order of reactivity of the thiols to the cyclic iminoethers was DBDT > OBDT > PETT, and that of the dicarboxylic acids to the cyclic iminoethers was succinic acid > adipic acid > sebacic acid.