According to the (1)H, (13)C and (15)N NMR spectroscopic data and DFT calculations, the E-isomer of 1-vinylpyrrole-2-carbaldehyde adopts preferable conformation with the anti-orientation of the vinyl group relative to the carbaldehyde oxime group and with the syn-arrangement of the carbaldehyde oxime group with reference to the pyrrole ring. This conformation is stabilized by the C-H...N intramolecular hydrogen bond between the alpha-hydrogen of the vinyl group and the oxime group nitrogen, which causes a pronounced high-frequency shift of the alpha-hydrogen signal in (1)H NMR (approximately 0.5 ppm) and an increase in the corresponding one-bond (13)C-(1)H coupling constant (ca 4 Hz). In the Z-isomer, the carbaldehyde oxime group turns to the anti-position with respect to the pyrrole ring. The C-H...O intramolecular hydrogen bond between the H-3 hydrogen of the pyrrole ring and the oxime group oxygen is realized in this case. Due to such hydrogen bonding, the H-3 hydrogen resonance is shifted to a higher frequency by about 1 ppm and the one-bond (13)C-(1)H coupling constant for this proton increases by approximately 5 Hz.

A general efficient route to hitherto inaccessible symmetric and asymmetric meso-CF(3)-BODIPY dyes has been developed. The key stages include the reduction of available 2-trifluoroacetylpyrroles to the corresponding alcohols which are further condensed with pyrroles. The method allows the BODIPY with 3(5)aryl(hetaryl) and 3,5-diaryl(hetaryl) substituents to be readily assembled. The BODIPY dyes synthesized fluoresce (Φ(f) = 0.56-1.00) in the 560-680 nm region.

Keywords: Acetylene / Heterocycles / X-ray absorption spectroscopy / UV/Vis spectroscopy / Fluorescence spectroscopy (10), and 2,6-dimethyl-3-(pyrrol-2-yl)-5-[2-(1-vinylpyrrol-2-yl)]pyridine (11) have been synthesized from the oximes of the corresponding diacetylpyridines in a one-pot procedure by treatment with acetylene in MOH/DMSO systems (M = Li, K) at 80-140°C under pressures of 25-30 atm, thus illustrating the applicability and general character of the reaction for synthesis of diverse dipyrrole-pyridine assemblies and their N-vinyl and acetyl derivatives. A stable 4·DMSO

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 (Ϸ3:1) at 0°C. The λ max 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, 1 H NMR spectroscopic and quantum chemical studies p)] show the E,anti,anti isomer of the dyes to be the most stable under

It has been discovered that the chemical shifts of carbon atoms in 13 C NMR spectra of oximes having pyrrolyl, furyl, benzofuryl, thienyl, and pyridyl rings as substituents are changed systematically on going from the E-to the Z-isomer. This makes it possible to use the indicated chemical shifts for establishing the configuration of oximes with heterocyclic substituents and studying the special features of their electronic structure.Keywords: oximes with heterocyclic substituents, 13 C NMR spectra, stereospecificity of shielding constants.The stereospecificity of NMR spectral parameters of aldoximes and ketoximes has been studied for several decades . In particular it is necessary to select investigations of 1 H, 13 C, and 15 N spectra of oximes having a heterocyclic substituent. The 1 H NMR spectra of furfural oximes were investigated in the earlier studies [4,5]. The most interesting data were obtained for oximes enriched with 15 N isotope, in which a dependence was discovered of the geminal 15 N-1 H coupling constant on the steric orientation of the unshared pair of the nitrogen atom [5]. Ideas on the stereospecificity of parameters of 15 N NMR spectra in 15 N-labeled furfural oximes were developed in [9, 12], in which the stereospecificity of the 15 N nuclear shielding constants, the geminal 15 N-13 C coupling constants, and the vicinal 15 N-1 H coupling constants was shown. The aim of the present work was to study the stereospecificity of the shielding constants of the carbon-13 nuclei in 13 C NMR spectra of the series of oximes 1-6 having various heterocyclic substituents.The chemical shifts of 13 C atoms of oximes 1-6, and also of model oximes 7a,b, are given in Table 1. Two-dimensional 1 H-13 C correlation procedures HSQC and HMBC were used to assign the signals in the 13 C NMR spectra. Configurational assignment of aldoximes 1 and 2 was made on the basis of the differences of the chemical shift values of the "oxime" proton for the E-and Z-isomers, taking into account that in the E-isomer _______ * Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. __________________________________________________________________________________________

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Alkyl-, aryl-and hetaryl ketones after a one-pot oximation and treatment with acetylene are converted to 2-mono-and 2,3-disubstituted NH-and N-vinylpyrroles with alkyl-, aryl-and hetaryl substituents in good yields. The oximation is effected using a NH 2 OH·HCl-NaHCO 3 system at room temperature. The reaction with acetylene is carried out in the presence of the KOH/DMSO superbase at 100 o C under atmospheric pressure.

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