1,3-Dipolar cycloaddition of methyl diazoacetate to methyl acrylate was investigated by kinetic 1 Н NMR spectroscopy. It was established that the mechanism of the process includes parallel formation of trans-and cis-dimethyl-4,5-dihydro-3H-pyrazol-3,5-dicarboxylates as a result of [3 + 2]-cycloaddition of methyl diazoacetate to methyl acrylate; the corresponding rate constants were denoted k 1t and k 1c . The reaction rate of the isomerization of 3Нpyrazolines to 4,5-dihydro-1H-pyrazol-3,5-dicarboxylate (3Н → 1Н-pyrazoline rearrangement) was found to be sensitive to both the methyl acrylate (k 2t , k 2c ) and 1Н-pyrazoline concentrations (k 3t , k 3c ). Kinetic analysis showed that the proposed scheme is valid for various reagent concentrations. The numerical solution of the system of differential equations corresponded to the reaction scheme and was used to determine the complete set of reaction rate 500 OVCHINNIKOV ET AL. constants (k (× 10 5 M -1 ·s -1 ), 298 K; solvent, benzene-d 6 ): k 1t = 2.3 ± 0.3, k 1c = 1.6 ± 0.2, k 2t = 1.1 ± 0.3, k 2c = 1.8 ± 0.5, k 3t = 1.2 ± 0.4, k 3c = 2.2 ± 0.7. C 2013 Wiley Periodicals, Inc. Int J Chem Kinet 45: 499-

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Синтезированы новые галогензамещенные орто-кетокарбоновые кислоты и их псевдохлорангидриды. По реакции электрофильного замещения впервые синтезированы и охарактеризованы полиариленфталиды, имеющие заместители (хлор-и бром-) в 4-положении фталидного цикла. Ключевые слова: псевдохлорангидриды орто-кетокарбоновых кислот, полиариленфталиды, электрофильное замещение, электропроводящие полимеры.

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The polyheteroarylenes of new type, called polyarylenediphthalides (PADPs), containing two adjacent phthalide groups regularly alternating with aromatic (heteroaromatic) fragments in the main chain have been developed. For obtaining PADPs, two approaches based on the dehalogenation reactions were used. In the first, polycondensation of the pseudo-acids chlorides was carried out that led to the polymers with random stereo configuration of diphthalide groups. In the second, stereospecific PADPs were formed using diastereoisomeric pure halogenated biaryl-3,3′-diphthalides (meso and racemic) as monomers that attach themselves to the growing polymer chain entirely keeping their stereo configuration. The obtained polymers start to soften and decompose at ≈350°C in inert atmosphere. Degradation of PADPs at deep carbonizing stages in the inert atmosphere is followed by formation of foamed coke with increased content of diamond-like carbon that possesses a high hardness (≥8 by Mohs scale).