Русский

Archive for July 28, 2017

Applied Catalysis: A, 2017, 542, 350-358

P.Mäki-Arvela, J.Zhu, N.Kumar, K. Eränen, A.Aho, J.Linden, J.Salonen, M.Peurla, A.Mazur, V.Matveev, D.Y.Murzin

“Solvent-free “green” amidation of stearic acid for synthesis of biologically active alkylamides over iron supported heterogeneous catalysts”

Applied Catalysis: A, 2017, 542, 350-358
DOI: 10.1016/j.apcata.2017.06.006

Stearoyl ethanolamine was synthesized by amidation of stearic acid with ethanolamine in solventless conditions. Iron containing heterogeneous catalysts supported on SiO2, Al2O3, Beta (BEA), ZSM-12 (MTW) and Ferrierite (FER) were used in this work. Sn-modified Ferrierite and H-Ferrierite were also studied for comparison. Fe-modified catalysts synthesized using solid state ion-exchange and evaporation impregnation methods, were thoroughly characterized with X-ray powder diffraction, scanning electron microscope, FTIR with pyridine, nitrogen adsorption, energy dispersive X-ray microanalysis and Mössbauer spectroscopy. The highest conversion was obtained with Fe-H-FER-20 at 140 °C in 1 h giving 61% conversion and 98% selectivity towards the desired amide. The catalytic performance in terms of turnover frequency per mole of iron was achieved with the catalyst exhibiting the largest amount of Fe3+ species, optimum acidity and a relatively low Brønsted to Lewis acid site ratio.

RSC Adv., 2017, 7, 10070-10073

A.S. Smirnov, D.N. Nikolaev, V.V. Gurzhiy, S.N. Smirnov, V.S. Suslonov, A.V. Garabadzhiu, P.B. Davidovich

“Conformational stabilization of isatin Schiff bases – biologically active chemical probes”

RSC Adv., 2017, 7, 10070-10073
DOI: 10.1039/c6ra26779c
source: http://pubs.rsc.org/en/Content/ArticleLanding/2017/RA/C6RA26779C#!divAbstract

Isatin Schiff base derivatives have a wide range of biological effects. Unfortunately, these compounds possess a serious topological shortcoming: the conformational E ⇆ Z interconversion. Two ways of conformation stabilization are reported here: complexation with metals that stabilize the E-conformer and substitution in the 4th position of the isatin core stabilizing the Z-form.

Eur. J. Org. Chem., 2017, 2587-2595

A. Stukalov, V.V. Sokolov, V.V. Suslonov, M.A. Kuznetsov

“Pyrazoles and C-Imidoylaziridines through [4+1] Annulation and [2+1] Cycloaddition of 1-Azabuta-1,3-dienes with a Synthetic Equivalent of Phthalimidonitrene”

Eur. J. Org. Chem., 2017, 2587-2595
DOI: 10.1002/ejoc.201700172

Oxidative addition of N-aminophthalimide to 1,2,4-triaryl-1-azabuta-1,3-dienes leads, in most cases, to the regiodefined formation of 1,3,5-triarylpyrazoles in moderate to good yields through [4+1] annulation. This transformation is supposed to proceed by nitrenoid attack onto a lone pair of electrons of the imine nitrogen atom to give the vinylazomethine imine, followed by its 1,5-electrocyclization into pyrazoline and further aromatization into pyrazole. Rare examples of 2-imidoyl-1-phthalimidoaziridines that are formed by competitive [2+1] cycloaddition onto the C=C bond were isolated in low yields for 1-azadienes with electron-deficient aryl substituents at the imine nitrogen atom.