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Oligomers of cholesterol vinyl ether (CVE) with methyl vinyl sulfide synthesized in the presence of cationic catalyst ВF3 OEt2 in up to 81% yield (Mn up to 5700) demonstrate optical activity exceeding that of CVE homopolymer, which is probably due to both conformational effects of the oligomer chain and chirality induction during the polymerization.

Oligomers of cholesterol vinyl ether with methyl vinyl sulfide were synthesized in up to 81% yield (Mn up to 5700) by cationic copolymerization of the indicated monomers in the presence of BF3 ‧ OEt2. The oligomers demonstrate optical activity exceeding that of cholesterol vinyl ether homopolymer.

Cationic copolymerization of cholesterol vinyl ether with N-allenylpyrrolidone yielded co-oligomers with molecular mass of 1200-2100. The polymerization of N-allenylpyrrolidone involves both 1,2- and 2,3-positions of the allenyl substituent to give four types of units as a result of prototropic isomerization of the initially formed structures. In the developed method, the composition of co-oligomers can be controlled and, hence, their hydrophilic/hydrophobic balance, solubility, and membranotropic properties can also be controlled to change the potential biological activity of the products.

Aminomethylation of 2-methyl(aryl)-, 2-aryl-3-alkylpyrroles, 4,5,6,7-tetrahydroindole and its 1-vinyl- and 1-benzyl-substituted derivatives with a mixture of 5% water-ethanol solution of formaldehyde and cyclic amine (pyrrolidine, piperazine, and morpholine) without catalyst at room temperature leads to the formation of the corresponding 2-aminomethylpyrroles and 2-aminomethyl-4,5,6,7-tetrahydroindoles in up to 92% yields. In reaction of 1-vinyl-4,5,6,7-tetrahydroindole with formaldehyde water solution and piperazine in a 60% yield 1,4-bis(1-vinyl-4,5,6,7-tetrahydroindol-2-yl)piperazine was obtained, a promising bifunctional monomer and a building block for the synthesis of new indole derivatives, in particular, of biologically active polymers. In the reaction of 2-methylpyrrole and 4,5,6,7-tetrahydroindole with formaldehyde and morpholine along with the С2-aminomethylation the 1-hydroxymethylation of the pyrrole ring was observed.

Acylethynylpyrroles, available via the transition metal-free coupling of pyrroles with acylhaloacetylenes are readily annelated with propargylamine in a one-pot step-wise procedure: catalyst-free heating (60–65 °C, 6–16 h) in DMSO and then keeping for 2.5 h with CuI at the same temperature. The products are pyrrolyl-pyridines isolated in good to excellent yields (56–94%). It is experimentally shown that dehydrogenation of intermediate dihydropyridine moiety is not resulted from the oxidation with DMSO (Me2S was not detected) or air (argon blanket) and is likely associated with the CuI catalysis.

The first representatives of a previously unknown class of highly reactive functionalized pyrrole compounds, 3-(pyrrol-2-yl)propiolaldehydes, have been synthesized by the transition metal-free, mechanoactivated ethynylation of pyrroles with 3-iodopropiolaldehyde using a solid K 2 CO 3 medium under mild conditions (room temperature, 4 h) in yields of up to 71%.

The oligomerization of N-vinylpyrroles (N-vinyl-4,5,6,7-tetrahydroindole, N-vinyl-2-[1-(1-4,5,6,7-tetrahydroindole)ethyl]-4,5,6,7-tetrahydroindole, N-vinyl-2-phenylpyrrole, N-vinyl-3-heptyl-2-phenylpyrrole, N-vinyl-2,3-diphenylpyrrole, and N-vinyl-2-(2-naphthyl)pyrrole) under the action of iodine vapor leads to the formation of iodine-containing oligomers with an iodine content of 17–52% and a yield of up to 99%. The oligomers are paramagnetic and possess conductivity; they are readily soluble in organic solvents (benzene, dioxane, and chloroform) and are stable up to 110–260°C.

Available NH-2-acylethynylpyrroles undergo annulation/aromatization with propargylamine in the presence of 1 equiv. of CuHal (Hal = Cl, Br, I) at 60–65 °C to afford 3-acyl-2-(pyrrol-2-yl)pyridines and their 5-halo analogues in 28–61 and 5–14% yields, respectively. The latter are assumed to be resulted from halohydrogenation of the intermediate Cu-pyrrolylpropargyl amino enones.

5-Trifluoroacetylpyrrole-2-carbaldehydes were synthesized by low-temperature trifluoroacetylation of pyrrole-2-carbaldehyde acetals using trifluoroacetic anhydride, with subsequent removal of the acetal protecting group by mild acid-catalysed hydrolysis. The hydrolysis was accompanied by the formation of a minor product, (1Е,4Е)-1,5-bis[5-(2,2,2-trifluoroacetyl)-1Н-pyrrol-2-yl]-1,4-pentadien-3-one, which was isolated and identified.

The data on the polymerization of N-vinylpyrroles published for the most part during the past decade are systematized and summarized. Radical, cationic, and anionic polymerization of the mentioned monomers, which became easily accessible owing to the discovery and systematic development of their direct one-step synthesis from ketoximes and acetylene in the superbasic catalytic system KOH/DMSO (the Trofimov reaction), are discussed. Special attention is given to the physicochemical properties of the polymers (conductivity, paramagnetism, photosensitivity, and optical characteristics).

Composite proton-conducting membranes in the form of interpolymer films are prepared in an aqueous medium from sulfo-acid-modified poly(ethylene glycol vinyl glycidyl ether) and poly(vinyl alcohol). The initial poly(hydroxysulfo acid) is synthesized through the radical polymerization of ethylene glycol vinyl glycidyl ether followed by modification with sodium sulfite via epoxy groups and treatment with a cationite in the H form. The proton-conducting membranes feature improved thermal stability (200–250°C), a breaking strength of 1.0–8.9 MPa, elasticity (a relative elongation at break of 1.0–8.2%), chemical resistance, and specific proton conductivity attaining 10−1 S/cm after doping with orthophosphoric acid.

Oligo(N-vinyl-4,5,6,7-tetrahydroindole-co-butyl vinyl ethers) have been synthesized through free-radical cooligomerization with a yield of 84%. The copolymers are readily soluble in organic solvents (benzene, 1,4-dioxane, chloroform, and tetrahydrofuran), stable up to 380–400°C, and paramagnetic. (The concentration of paramagnetic centers is 1014 spin/g.) In addition, the copolymers exhibit the properties of organic semiconductors. (After being doped with iodine, σ = 1.1 × 10−7 S/cm.) The analysis of the 1H and 13C NMR spectra has shown that the oligomerization reaction is complicated by intramolecular cyclization involving carbon atoms located at the 2-position of pyrrole rings.

Phenylferrocenylacetylene was found to be capable of oligomerizing in the presence of WCl 6 (130 °C, 24 h) to afford short polyenes (with about 5 monomer units in the macromolecule) in up to ∼30% yield. The polyenes synthesized are promising reactive macromonomers and building blocks for high-tech materials.

Cationic polymerization of N-vinyl-2,3-diphenylpyrrole (FeCl3·6H2O, complex LiBF4–dimethoxyethane, WCl6, BF3·OEt2, Me3SiCl, 2 wt%, benzene, 20–80 °C, 24–48 h) affords oligomers with alternating pyrrole and ethylydene units in up to 61% yields (molecular weight 800–3100). Free radical polymerization of this monomer (AIBN, 0.5–5 wt%, benzene, 80 °C, 1–50 h) leads to oligomers having polyethylene backbone with pendant 2,3-diphenylpyrrole moieties (in up to 92% yield, molecular weight 2100–2500). The oligomers show semiconducting (σ = 2.6 × 10−7–4.2 × 10−6 S/cm after doping with I2) and paramagnetic (N = 1.2 × 1018–4.8 × 1019 spin/g) properties and fluoresce in the region 383–388 nm (solution in dioxane).

Polyfunctional reactive copolymers of N-vinylpyrrole-2-carbaldehydes with styrene, N-vinylpyrrolidone, and ethylene glycol vinyl glycidyl ether are synthesized in the presence of AIBN (2 wt %, 80°C, 50 h) with a yield of up to 98% and a molecular mass of up to 4800. The copolymers show paramagnetic behavior (N = 2.0 × 1015−2.0 × 1017 g−1) and possess the properties of organic semiconductors (σ = 0.9 × 10−11–2.8 × 10−7 S/cm after doping with I2).

A novel long-chain divinyl ether of tris(diethyleneglycol)-bisacetal, has been synthesized by electrophilic addition of one molecule of diethylene glycol to two molecules of divinyl ether of diethylene glycol (DVDEG) in the presence of CF3COOH in quantitative yield. The monomer was cationically polymerized (BF3·OEt2, or complex LiBF4·MeO(CH2)2OMe) and copolymerized with DVDEG to deliver solid polymers the yields being 80–100%. The polymers represent the cross-linked polyether-polyacetal structures comprising macrocycles. The polymers were treated with 3% solution of KOH or CsOH in methanol to afford solid superbase complexes of KOH (CsOH) with cross-linked polyether-polyacetal macrocyclic networks. Preliminary tests have shown the complexes to be active catalysts for ethynylation of acetones and prototropic isomerization of methyl propargyl ethers to allenyl methyl ethers. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

The protected bis(hydroxyorganyl) polysulfides synthesized have been tested as modifiers of electrolyte of lithium-sulfur rechargeable batteries. The best result (35% increase of the battery capacity at the 50th cycle) was attained using 5 wt.% of 2,2,12,12-tetramethyl-4,10-diphenyl-3,11-dioxa-6,7,8-trithia-2,12-disilatridecane. Bis(hydroxyorganyl) polysulfides protected at the hydroxyl group have been synthesized for the first time by the reaction of oxiranes with sodium polysulfide (ethanol, NaHCO 3 , 12 h, 20–25 °C) in yield 21–87%. For the hydroxyl protection in the hydroxy polysulfides, the acetal, tri(methyl)silyloxy or tri(ethoxy)silyl protecting groups were employed.

Cationic polymerization of N-vinyl-2-phenylpyrrole (catalysts: Me3SiCl, CF3COOH, BF3·OEt2, HCl, WCl6, FeCl3, complex LiBF4–dimethoxyethane, catalysts concentration 1–2 wt%, 20–70 °C, 24–48 h) affords oligomers (molecular weight 1400–1700) of a unexpected structure with alternating 2-phenylpyrrole and ethylydene units, the yields reaching 63%. The oligomers structure has been supported by isolation and identification of the corresponding dimer, N-vinyl-2-phenyl-5-[N-(2-phenyl-1H-pyrrol-1-yl)ethyl]-1H-pyrrole. Radical polymerization of the same monomer (AIBN, 1.5–4 wt%, 60–80 °C, 40–60 h or UV irradiation or both) gives oligomers (molecular weight 2100–3000) of normal structure having polyethene backbone with pendant 2-phenylpyrrole groups in up to 40% yields. The oligomers of both types are semiconductors (1.3 × 10−6–3.6 × 10−6 S/cm) after doping with I2, paramagnetic (4.2 × 1017–8.7 × 1017 g−1) and fluorescent in a near UV region (λ 355–363 nm, acetonitrile).

Polymers of 1,4-bis[2-(N-vinyl)pyrrolyl]benzene with free N-vinyl groups in side chains are synthesized in the presence of AIBN (2–5 wt %, 70°C) with a yield of up to 34% and a molecular mass of up to 11.5 × 103. In the presence of cationic catalysts (Me3SiCl, the LiBF4-dimethoxyethane system, and BF3 · OEt2), 1,4-bis[2-(N-vinyl)pyrrolyl]benzene gives macromolecules with alternating 1,2-pyrrolene and ethylidene units in the backbone with yields of 80, 44, and 33%, respectively. The polymers demonstrate paramagnetic and luminescent properties.

I 2 -doped and pyrrole ring-iodinated semi-conducting oligomers of N-vinyl-3-alkyl-2-phenylpyrroles have been synthesized by free-radical polymerization of the above monomers (AIBN, 2–5 wt%, 60–80 °C) and further exposure of the oligomers obtained to I 2 vapor. The parent oligomers exhibit paramagnetic and fluorescent properties and stable up to 300–370 °C.

Sterically hindered 2,5-diphenyl-and 2,3,5-triphenyl-1-vinylpyrroles have been obtained by the vinylation of the corresponding NH-pyrroles with acetylene in superbasic catalytic system KOH—DMSO in up to 78% yield. 2,3,5-Triphenyl-1-vinylpyrrole has also been obtained in 75% yield by the regioselective bromination of 2,3-diphenyl-1-vinylpyrrole with subsequent cross-coupling of 5-bromo-2,3-diphenyl-1-vinylpyrrole with phenylmagnesium bromide in the presence of dichloro[1,1′-bis(diphenylphosphino)ferrocene]palladium(II). 2,5-Diphenyl- and 2,3,5-triphenyl-1-vinylpyrroles undergo a free-radical polymerization (AIBN, 80 °C) to form oligomers in 11 and 27% yield, respectively.

The radical copolymerization of vinyl chloride with 2-methyl-5-vinylpyridine and 1-vinyl-4,5,6,7-tetrahydroindole is accompanied by dehydrochlorination. In the vinyl chloride-2-methyl-5-vinylpyridine system, the evolved hydrogen chloride interacts with a pyridine hydrogen atom to give charged units of a heterocycle. In the vinyl chloride-1-vinyl-4,5,6,7-tetrahydroindole system, the hydrogen chloride being formed initiates the cationic dimerization of a nitrogen-containing monomer. The synthesized copolymers based on vinyl chloride surpass the commercial poly(vinyl chloride) in terms of thermal stability and solubility in organic solvents.

Reactive linear and crosslinked copolymers of diethylene glycol divinyl ether and ethylene glycol vinyl glycidyl ether with methyl vinyl sulfide have been synthesized in the presence of 2,2′-azobis(isobutyronitrile) (2%, 60 °C, 45–55 h) in ∼53% yield. The hydrolyzed at the residual vinyloxy and epoxy groups and oxidized at the methylthio groups copolymers upon treatment with KOH afford alkoxide (complex) and crown-like superbases. They are capable of catalyzing the acetone ethynylation, as well as the prototropic isomerization of methyl propargyl ether to allenyl methyl ether and vinylation of ethylene and diethylene glycols with acetylene.

Nanoporous (11–12 nm) crosslinked macrocyclic polyethers with vinyloxy and hydroxyl groups have been synthesized by the free-radical polymerization of diethylene glycol divinyl ether (AIBN, 80°C, i-octane), followed by acidic hydrolysis. It has been shown that the polymers react with KOH to form insoluble superbase complexes and alcoholates capable of catalyzing vinylation of ethylene glycol by acetylene.

2-Arylazo-1-vinylpyrroles (a new group of azo dyes of the pyrrole series) are polymerized under heating (80°C) without initiators and in the presence of AIBN to form intensely colored paramagnetic and conducting polymers with a yield of 92%. By the example of the thermal copolymerization with 1-vinylpyrrolidone, it has been shown that 2-arylazo-1-vinylpyrroles may simultaneously play the roles of initiators and comonomers.

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.

Vinyl ether of cholesterol has been polymerized through the free-radical mechanism with a yield of up to 30% to obtain optically active soluble oligomers. By the example of acrylonitrile, N-vinylpyrrolidone, ethylene glycol vinyl glycidyl ether, and N-vinyl-4,5,6,7-tetrahydroindole, it has been established that optically active copolymers of cholesterol may be synthesized.

5-Acylethynylpyrrole-2-carbaldehydes have been synthesized from the protected pyrrole-2-carbaldehydes by their transition-metal-free topochemical mechanoactivated ethynylation with acylbromoacetylenes in a solid Al2O3 medium (room temperature, 6 h, 41–54% yields).

5-Acylethynylpyrrole-2-carbaldehydes have been synthesized from the protected pyrrole-2-carbaldehydes by their transition-metal-free topochemical mechanoactivated ethynylation with acylbromoacetylenes in a solid Al2O3 medium (room temperature, 6 h, 41–54% yields).

New reactive dyes, 2-arylazo-1-vinylpyrroles, have been synthesized in 52–94 % yield by a modified azo coupling of readily accessible 1-vinylpyrroles with arenediazonium hydrocarbonates in aqueous ethanol (≈3:1) at 0 °C. The λmax values for the UV/Vis absorption of the dyes ranges from 377.8–480.6 nm with log ϵ = 4.11–4.99, and this strongly depends on the substituent structure both in the pyrrole and the benzene ring, and is indicative of highly polarizable and tunable chromophores. X-ray, 1H NMR spectroscopic and quantum chemical studies [B3LYP/6-311 (d,p)] show the E,anti,anti isomer of the dyes to be the most stable under normal conditions. The dyes are reversibly protonated and complex to BF3 with a color change. Their copolymerization across the vinyl group affords intrinsically colored copolymers. They have also been shown to act as good ligands in the Pd-catalyzed Heck alkene arylation. Thus, the properties of the novel dyes are promising for creating new molecular switches, memory and recording devices, acid-base and metal sensors, as well as transition-metal complex catalysts.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)

Polyfunctionalized linear copolymers of N-allenylimidazole and di(ethylene glycol) divinyl ether with polyconjugated (polyvinylene) blocks in the main chain and exomethylene bonds and vinyloxyethoxyethyl groups in the side chain were prepared. Using the reaction of the copolymers with CuCl2, a possibility of synthesis of polymeric metal complexes for catalysis of organic reactions was shown. The IR and ESR spectra of the complexes were studied.

Bis-[3-(vinyloxyethoxy)-2-hydroxypropyl-]polysulfides (BVPS) have been prepared by reacting ethylene glycol vinyl glycidyl ether (EGVGE) with Na2S4 in the presence of NaHCO3 and a phase transfer catalyst, triethylbenzylammonium chloride. The polysulfides obtained are inactive in radical polymerization but polymerize readily upon thermal initiation (140°C, 1 h) or in the presence of cationic catalysts [BF3·OEt2, CF3COOH, H(AuCl4)·4H2O, LiBF4-dimethoxyethane, 20–70°C]. Polymerization leads to the formation of crosslinked polymers. It has been shown that BVPS and their polymers can be used as active binders in cathode compositions of lithium–sulfur power sources. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 4051–4055, 2006

1-Allenylpyrroles are polymerized under the conditions of thermal (60 °C) and radical initiation at both 1,2- and 2,3-positions of the allenyl group to form soluble reactive polymers with various ethylenic, including polyvinylic, fragments. The possibility to prepare 1-allenylpyrrole copolymers has been demonstrated using 1-vinylpyrrolidone and ethylene glycol vinylglycidyl ether as an example. Doped layers based on poly-1-allenyl-4,5,6,7-tetrahydroindole are photosensitive.

Polyacetylene functionalized by sulfoxide groups was synthesized from poly(methyl vinyl sulfoxide) by the elimination of methanesulfenic acid under the action of a strong base at 20—50 °C.

Treatment of the title oxiranylmethylindole (I) with the formylating reagent system DMF/(COCl)2 starts with oxirane ring opening [(II)] followed by formylation of the pyrrole ring [(IV)] and ends with the rather unexpected formylation of the hydroxy group in (IV) [(V)].

In the presence of Bronsted and Lewis acids, I-vinyl-4,5,6,7-tetrahydroindole is transformed into its dimes, 1-vinyl-2-[1-(4,5,6,7-tetrahydroindolyl)ethyl]-4,5,6,7-tetrahydroindole, and polymers containing units of the dimer and segments of oxidized tetrahydroindole cycles.

In the presence of Bronsted and Lewis acids, I-vinyl-4,5,6,7-tetrahydroindole is transformed into its dimes, 1-vinyl-2-[1-(4,5,6,7-tetrahydroindolyl)ethyl]-4,5,6,7-tetrahydroindole, and polymers containing units of the dimer and segments of oxidized tetrahydroindole cycles.

Treatment of 1-(2-oxiranylmethyl)-4,5,6,7-tetrahydroindole with the DMF/(COCl)2 reagent system in CH2Cl2 (room temperature, 40 min) starts oxirane opening to give 1-(3-chloro-2-hydroxypropyl)-4,5,6,7-tetrahydroindole followed by the formylation of the pyrrole ring to end up with the formation of 1-(3-chloro-2-formyloxypropyl)-4,5,6,7-tetrahydroindole-2-carboxaldehyde viathe intermediate 1-(3-chloro-2-hydroxypropyl)-4,5,6,7-tetrahydroindole-2-carboxaldehyde.

1-Vinyl-4,5,6,7-tetrahydroindole in the presence of Bronsted acids (HCl, H2SO4, HOAc) and Lewis acids (BF3 · OEt2, FeCl3, TiCl3, SnCl4, SiCl4, Et3SiCl, Me2, PhMeSiCl2) undergoes an alternative oligomerization involving both the double bond and the α-position of the pyrrole ring to form the dimer 1-vinyl-2-[1-(4,5,6,7-tetrahydro-1-indolyl)ethyl]-4,5,6,7-tetrahydroindole in a yield up to 68% and oligomers of the same backbone, soluble (major product) and insoluble (minor product) in hot hexane, the latter being enriched by oxidized and hydrolyzed tetrahydroindole units. The molecular weights of the former oligomers were assessed from 1H NMR spectra to range from 1000 to 2000.

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.