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Reakcje asymetrycznego otwierania pierścienia azyrydyn

Prusinowska N.

Wiadomości Chemiczne

2013

[Z] 67, 5-6

585--618

Aziridines, the nitrogenous analogues of epoxides, are useful building blocks for the synthesis of various functional materials and biologically active compounds. The reactivity of aziridines toward ring opening and expansion is dependent upon their extremely strained ring structures. Among the procedures of ring opening of aziridines, a nucleophilic ring-opening reaction is one of the major routes to highly functionalized compounds (Scheme 2). This short review focused on essentiac asymmetric ring opening reactions of aziridines including enantioselective ring opening of meso-aziridines and kinetic resolution of racemic aziridines with various hetero and carbon nucleophiles towards the synthesis of highly enantiomerically enriched 1,2-difunctionalized fine chemicals.

Substrate inhibition in lipase-catalysed transesterification of mandelic acid with vinyl acetate

Dąbkowska K., Pilarek M., Szewczyk K. W.

Chemical and Process Engineering

2012

Vol. 33, nr 4

539--546

Kinetic resolution of (R)- and (S)-mandelic acid by its transesterification with vinyl acetate catalysed by Burholderia cepacia lipase has been studied. The influence of the initial substrate concentration on the kinetics of process has been investigated. A modified ping-pong bi-bi model of enzymatic transesterification of (S)-mandelic acid including substrate inhibition has been developed. The values of kinetic parameters of the model have been estimated. We have shown that the inhibition effect revealed over a certain threshold limit value of the initial concentration of substrate.

Lipase-Catalysed Resolution of 1-Hydroxyethane-P-phenylphosphinates

Majewska P., Kafarski P., Lejczak B.

Polish Journal of Chemistry

2005

Vol. 79 / nr 3

561-566

Lipase-catalysed hydrolysis and transesterification were used to obtain _-hydroxyalkanephosphinates with two stereogenic centers, namely at_-carbon and phosphorus atoms. These compounds were chosen to check if there is a transfer of chirality from carbon to phosphorus atom during lipase catalysed reactions.

Biogenetically Patterned Enantioselective Synthesis

Goldenstein K., Nerenz F., Winterfeldt E.

Polish Journal of Chemistry

1999

vol. 73 nr 1

3-14

Bioenergetically oriented enantioselective syntheses of the bicyclic-ether substructure of Azadirachtin and of the spirocyclohexenone building block for the Agelorines are communicated. In the first case the kinetic resolution of a cyclopentenone starting material is exercised in a high pressure Diels-Alder cycloaddition and in the second case the cycloadduct of a prochiral spirocyclohexadienone is used for the differentiation of enantiotopic groups.

Synthesis of P-chiral, non-racemic phosphinylacetates via enzymatic resolution of racemates

Kiełbasiński P., Żurawiński R., Pietrusiewicz K.M., Zabłocka M., Mikołajczyk M.

Polish Journal of Chemistry

1998

Vol. 72, nr 3

564-572

A series of racemic methyl phosphinylacetates was hydrolyzed in the presence of porcine liver esterase (PLE) under the kinetic resolution conditions to give the corresponding P-chiral phosphinylacetic acids and recovered esters in high enantiomeric purity (72-100%ee). The Jones' active site model was applied to explain the enantioselectivity of the reaction.