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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

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)

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

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.

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.

The vinyltetrahydroindole (I) is coupled with equimolar amounts of the phenols (II) in the absence of a catalyst to give the phenoxyethyltetrahydroindoles (III).