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Polimery z odciskiem molekularnym jako biomimetyki metaloenzymów

Czulak J., Trochimczuk A., Marcinkowska A.

Wiadomości Chemiczne

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2014

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[Z] 68, 9-10

783--809

EN

This paper presents methods of the synthesis and applications of biomimetic catalytic systems produced from molecularly imprinted polymers (MIP). MIPs contain cavities, which are complementary to the imprinted template, thus possess high selectivity and affinity for the molecules resembling template. MIPs have various applications such as: sorption, chromatography, solid phase extraction, drugs transport and catalysis. However, this article is a review of catalytic systems containing in their active sides one of the selected metal ions: copper(II), cobalt(II), zinc(II), iron(III) or nickel(II). Presented catalytic systems are used in hydrolysis, oxidations, hydrogenations and aldol condensation reactions. This review deals with papers published till 2013.

2

Microwave assisted sulphated titania catalyzed aldol condensation: Synthesis of some (E) 3-(2-naphthyl)-1-(substituted phenyl)-2-propen-1-ones under solvent-free conditions

Janaki P., Sekar K. G., Thirunarayanan G.

International Letters of Chemistry, Physics and Astronomy

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2014

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Vol. 9

16--22

EN

A series of titled chalcones were synthesized by aldol condensation between 2-naphthaldehyde and various substituted acetophenones using solid acidic solid sulphated titania catalyst under microwave irradiation. The yields of these chalcones are more than 90 %. The synthesized chalcones are characterized by their physical constants, analytical and spectroscopic data.

3

Catalytic Transfer Hydrogenation of Cycloalkanones on MgO. Vapour and Liquid Phase Modes of Reaction

Gliński M.

Polish Journal of Chemistry

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2009

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Vol. 83, nr 2

187-194

EN

The reactivity of a series of cycloalkanones of the general formula (CH2)nCO, where n = 4, 5, 6, 7, 11 and 14 in the transfer hydrogenation reaction over magnesium oxide as the catalyst, either in vapour or liquid phase (VP or LP) has been studied. In the VP mode of reaction the activity of MgO treated with triethylamine, water, phenol or benzoic acid in the reduction of cyclopentanone by propan-2-ol has been determined. A strongly diminished or residual activity of MgO has been observed after the catalyst's treatment with phenol or benzoic acid, respectively. The occurence of side reactions of cyclopentanone in the LP mode of reaction resulted in high conversions of the ketone (up to 91%), very low yields of cyclopentanol (I) (be low 6%) and very high yields of 2-cyclo pentylidene-cyclopentanone (II) (greater than 80%).

4

Selektywne reakcje kondensacji acetonu i acetofenonu w układach katalitycznych wspomaganych mechanochemicznie

Kijeński J., Śmigiera E., Migdał A. R., Osawaru O., Nemtusiak M., Ostrowski S.

Przemysł Chemiczny

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2007

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T. 86, nr 4

330-336

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Formation of active sites in thermally treated hydrotalcite-based catalysts for acetone aldolization

Kuśtrowski P., Sułkowska D., Chmielarz L., Paczyńska J., Dziembaj R.

Polish Journal of Chemical Technology

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2005

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Vol. 7, nr 1

33-37

EN

Mg-AI hydrotalcite containing CO3(2-) and NO3(-) as interlayer anions was synthesized according to the coprecipitation method at constant pH (9.0) and temperature (50°C), and then transformed into mixed metal oxides by calcination at 450, 500, 550 or 600°C for 8 h. The as-prepared hydrotalcite-like sample was characterized with respect to its structure (XRD), chemical composition (XRF, elemental analysis) and thermal stability (EGA-MS). Moreover, the textural features of the thermally activated hydrotalcite were examined using low-temperature (77 K) sorption of N2. Changes in the acid-base properties of the precursor calcined at different temperatures were studied by means of temperature-programmed desorptions of NH3 and CO2. It was found that the hydrotalcite-like sample calcined at 450°C, containing a part of non-decomposed interlayer anions, showed a rather low concentration of acidic and basic surface sites. The increase in the calcination temperature caused the removal of the interlayer anions, and an increase in the concentration and strength of the acidic and basic surface centers. The formation of high number of acid/ base surface sites resulted in raising the catalytic activity of the calcined hydrotalcites in the liquid-phase aldol condensation of acetone.

6

Production of isophorone by the vapour-phase self-condensation of acetone over the hydrotalcite-derived catalysts

Kuśtrowski P., Sułkowska D., Chmielarz L., Cap S.

Polish Journal of Chemical Technology

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2004

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Vol. 6, nr 4

41-46

EN

The magnesium-aluminum precursor with the structure of hydrotalcite, confirmed by XRD and FTIR, was transformed into mixed metal oxides by a thermal activation at 450, 500, 550 or 600°C for 16 h. The obtained catalysts were characterized with respect to their textural properties (surface area, total porosity and pore size distribution) and used in the gas-phase aldolization of acetone. The effect of reaction temperature and calcination conditions on the catalytic performance was studied. The highest initial conversion of acetone (87.1%) with the selectivity to isophorone of 89.7% was measured for the hydrotalcite-derived Mg-Al oxides calcined at 600°C in the reaction carried out at 240°C.