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Ciecze jonowe oraz potencjalne obszary ich zastosowań w przemyśle chemicznym

Borowiecki P., Bretner M., Plenkiewicz J.

Wiadomości Chemiczne

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2015

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[Z] 69, 3-4

271--296

EN

Ionic liquids (ILs) compose a group of chemical compounds of ionic nature consisting of organic cation and inorganic or organic anion, whose melting point does not exceed 100°C (373,15 K). These compounds play a very important role in scientific investigations as well as in industrial organic synthesis, both in high‑ -tonnage productions as well as low-tonnage technologies of high added-value chemicals and materials. Ionic liquids are mostly used as alternative media and/or catalysts for desired chemical reactions. Multifunctionality and popularity of ionic liquids applications mainly stems from their beneficial physicochemical properties, such as: (i) very low vapor pressure, (ii) negligible viscosity, (iii) high overall- and thermal-stability, (iv) incombustibility and non-explosiveness, (v) high heat capacity, (vi) good solubility of most organic compounds (including polymers) as well as organometallic and inorganic compounds (including gases), (vii) low compressibility, and (viii) high electrochemical conductivity. Moreover, ionic liquids (x) exist in liquid state in a very wide range of temperature, (xi) exhibit a wide range of electrochemical stability as well as (xii) improve properties of enzymes and other biocatalysts, positively impacting on their activity, stability, enantioselectivity and/or stereoselectivity. It is worth noting that ionic liquids increasingly constitute a target products of defined commercial characteristics, such in the case of: electrochemicals, chemo-therapeutics, environmental anti-degradation agents, effective and safe agrochemicals etc. In this review, with 238 refs., development trends and potential applications of ionic liquids is presented.

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Katalizowane enzymami reakcje estryfikacji i redukcji - otrzymywanie optycznie czynnych alkoholi

Plenkiewicz J.

Prace Wydziału Inżynierii Chemicznej i Procesowej Politechniki Warszawskiej

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2000

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Vol. 26, z. 2

19-29

PL

Przedstawiono kierunki badań prowadzonych w Zakładzie Technologii i Biotechnologii Środków Leczniczych, których celem było otrzymanie optycznie czynnych alkoholi, posiadających drugą reaktywną chemicznie grupę funkcyjną. Jako chiralne katalizatory wykorzystano izolowane enzymy oraz cale komórki drożdżowe (Saccharomyces cerevisiae). Otrzymane optycznie czynne związki mogą być wykorzystane jako chiralne syntony w dalszych syntezach, prowadzących do otrzymania leków lub pestycydów, lub jako pomocniki chiralne w asymetrycznej syntezie.

EN

The main directions of the investigations carried out in the Department of Drugs Technology and Biotechnology, aimed at the preparation of optically active alcohols with second reactive substituent, are presented. Isolated enzymes as well as whole yeast cells (Saccharomyces cerevisiae) were used as the chiral catalysts. The obtained optically active compounds can be used as chiral synthons in further syntheses leading to biologically active substances or as chiral auxiliaries in an asymmetric synthesis.

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Zastosowanie lipaz w syntezie organicznej w środowisku bezwodnym

Chalecki Z., Plenkiewicz J.

Wiadomości Chemiczne

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1998

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[Z] 52, 7-8

545-568

EN

In nature the enzymatic reactions are conduced in aqueous media. However for the purpose of organic synthesis nonaqueous conditions such as organic solvents are more suitable regarding reagents stability and reaction equilibrium. Rapidly increasing number of enzyme-catalysed processes shows great possibility of this domain of chemistry. This review presents methods that have been used in lipase-catalysed esterifications and transenterifiacations in nonaqueous media. We show many examples of resolution of racemic alcohols and acids using different lipases in different reaction conditions. We also present a few examples of highly regioselective properties of lipases. There are descibed general principles that govern lipase-catalysed reactions and historical development of biocatalysis in organic synthesis. We hope that this review will be helpful for the investigators and students in solving their problems of enzymatic synthesis.