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Chromatographic Separation of Enantiomers

Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences, Tbilisi State University, Georgia [Pg.75]

After its discovery in 1848 by the French scientist Luis Pasteur [1], chirality as a phenomenon has served and continues to serve as a source of inspiration for generations of chemists. Undoubtedly, this is an exciting [Pg.75]

A chiral molecule is a type of molecule, that lacks an internal plane of symmetry and has a nonsuperimposable mirror image. The chiral molecules contain the elements (center, axis, or plane) of chirality. The chiral molecule that contains only one element of chirality may exist in two possible configurations, which are not superimposable. These compounds with different stereochemical configurations are called enantiomers. [Pg.76]

A growing number of examples of dramatic, sometimes even fatal differences between the biological activities of enantiomers led to the release of regulatory guidelines in many coimtries that consider one enantiomer as the impurity of another enantiomer. This requires manufacturers of chiral compounds to perform an independent investigation of both enantiomers [3]. Separation of enantiomers is important from the viewpoint of both accessing chiral compounds in enantiomerically pure form and determining enantiomeric purity (composition) of chiral compoimds. [Pg.76]

Separation of enantiomers by nonchromatographic methods, such as catalysis or crystallization, is based on chemical transformation or phase transition. Both of these are one-step processes, while chromatography is a multistep separation method. This means that the overall resolution of the solutes originates from a large number of stereoselective one-step adsorption—desorption cycles. The cumulative nature of the chromatographic separation is the reason that a free energy difference in interactions of enantiomers with a chiral selector as small as 0.025 kj/mol may. [Pg.76]


TYPICAL HOMOCHIRAL DERIVATIZING REAGENTS FOR GAS CHROMATOGRAPHIC SEPARATION OF ENANTIOMERS... [Pg.456]

Francotte, E. and Junker-Buchheit, A., Preparative chromatographic separation of enantiomers, /. Chromatogr., 576, 1, 1992. [Pg.51]

The chiral recognition ability of a CSP is quantitatively evaluated from the results of chromatographic separation of enantiomers. Figure 3.4 shows a chromatogram of the resolution of benzoin (19) on cellulose tris(3,5-dimethylphenylcarbamate). The (+)-isomer elutes first followed by the (—)-isomer complete baseline separation is achieved. The results of the separation can be expressed by three parameters—capacity factors (k1), separation factor (a), and resolution factor (Rs)—defined as follows ... [Pg.159]

For initial work on cyclodextrin-mediated chromatographic separation of enantiomers, see Hinze, W. L. Armstrong, D. W. ed. Ordered Media in Chemical Separations, ACS Symposium Series 342, 1986. [Pg.68]

Cyclodextrin-mediated chromatographic separation of enantiomers is also discussed in Braithwaite, A. Smith, F. J. Chromatographic Methods, 5th Edition, Blackie Academic Professional, London, New York, 1996. [Pg.68]

Recent advances in gas chromatographic separations of enantiomers allow precise determination of the enantiomeric purity of the algal pheromones. The czs-disubstituted cyclopentenes, such as multifidene, viridiene, and caudoxirene, are of high optical purity [ 95% enantiomeric excess (e.e.)] whenever they have been found (32,33). The situation is different with the cyclopropanes and the cycloheptadienes, as shown in Table 2 and Figure 1. Hormosirene from female gametes or thalli of... [Pg.101]

Elargitai, T., Kaida, Y., and Okamoto, Y., Preparation and chromatographic evaluation of 3,5-dimethylphenyl carbamoylated beta-cyclodextrin stationary phases for normal-phase high-performance liquid-chromatographic separation of enantiomers, J. Chromatogr., 628, 11, 1993. [Pg.165]

Peter, A., Torok, G., and Armstrong, D.W., High-performance liquid chromatographic separation of enantiomers of unusual amino acids on a teicoplanin chiral stationary phase, J. Chromatogr. A, 793, 283, 1998. [Pg.169]

Schurig V, Nowotny HP, Gas chromatographic separation of enantiomers on cyclodextrin derivatives, Angew Chem 29, 939—957, 1990. [Pg.177]

Bicchi C, D Amato A, Rubiolo P, Cyclodextrin derivatives as chiral selectors for direct gas chromatographic separation of enantiomers in the essential oil, aroma and flavor J Chromatogr A 843 99-121, 1999. [Pg.177]

Takahisa E, Engel K-H (2005) 2,3-Di-0-methoxymethyl-6-0-tert-butyldimethysilyl-)6-cyclo-dextrin, a useful stationary phase for gas chromatographic separation of enantiomers. J Chromatogr A 1076 148... [Pg.403]

Ionic liquids are low-melting salts that have very low volatility. An optically active ionic liquid can be the stationary phase for gas chromatographic separation of enantiomers. J. Ding, T. Welton, and D. W. Armstrong, Chiral Ionic Liquids as Stationary Phases in Gas Chromatography, Anal. Chem. 2004, 76, 6819. [Pg.680]

The evolution of CDs as chiral selectors in the liquid chromatographic separation of enantiomers has been a subject of interest for the last two decades. The presence of the chiral hollow basket, or cavity, makes these molecules suitable for the chiral resolution of a wide range of racemic compounds. At present, the use of CDs as chiral selectors for enantiomeric resolution by liquid... [Pg.103]

Pirkle WH, Finn JM, Hamper BC, Schreiner J, Pribish JR, A useful and conveniently accessible chiral stationary phase for liquid chromatographic separations of enantiomers, in Asymmetric Reactions and Process in Chemistry, Eliels EL, Otsuka S (Eds.), ACS Symposium Series No. 185, American Chemical Society, Washington DC, p. 245 (1982). [Pg.218]

Persson and Andersson [65] reviewed the unusual effects in liquid chromatographic separations of enantiomers on chiral stationary phases with emphasis on polysaccharide phases. On protein phases and Pirkle phases, reversal of the elution order between enantiomers due to... [Pg.216]

Schurig, V. (1984) Gas chromatographic separation of enantiomers on optically active metal-complex-free stationary phases. Angew. Chem. Int. Ed. 23, 747-765. [Pg.298]

Pirkle, W.H. and Pochapsky, T.C. (1989) Considerations of chiral recognition relevant to the liquid chromatographic separation of enantiomers, Chem. Rev. 89, 347-362. [Pg.318]

Tachibana, K. and Ohnishi, A. (2001) Reversed-phase liquid chromatographic separation of enantiomers on polysaccharide type chiral stationary phases, J. Chromatogr. A 906, 127-154. [Pg.320]

Armstrong, D.W., Chiral stationary phases for high performance liquid chromatographic separation of enantiomers a mini-review,./. Liq. Chromatogr., 7, 353, 1984. [Pg.147]

C. Pettersson, Chromatographic separation of enantiomers of acids with quinine as chiral counter ion, J. Chromatogr., 316 553 (1984). [Pg.105]

W. H. Pirkle, M. H. Hyun, A. Tsiporas, B. C. Hamper, and B. Banks, A rational approach to the design of highly effective chiral stationary phases for the liquid chromatographic separation of enantiomers, J. Pharm. Biomed. Anal., 2 173 (1984). [Pg.105]

More than 30 years ago, Bill Pirkle, the recognized inventor of modern chiral HPLC, realized that it may be possible to effect a chromatographic separation of enantiomers by use of chiral selectors (or ligands) bound to a silica matrix 3 3,3 4]. There has been a phenomenal amount of development in chiral stationary phases over subsequent years but, a relatively small number of... [Pg.44]

The gas chromatographic separation of enantiomers or diastereoisomeric. derivatives, of 4-hydroxyacids and... [Pg.47]

S. Allenmark, B. Bomgren, and H. Boren, Direct liquid chromatographic separation of enantiomers on immobilized protein stationary phases III. Optical resolution of a series of A-aroyl d, 1-amino acids by high-performance liquid chromatography onbovine serum albumin covalently bound to silica, /. Chromatogr. 264 (1983), 63-68. [Pg.137]

Inclusion complexing partners are classified as hosts and guests [46]. There are two types of hosts that were successfully employed in the chromatographic separation of enantiomers hosts that have a hydrophobic interior and hosts with a hydrophilic interior. The hydrophilic interior means that the cavity contains heteroatoms such as oxygen, where lone-pair electrons are able to participate in bonding to electron acceptors such as an organic cation (e.g., chiral crown ethers). In contrast, a host with a hydrophobic interior cavity is able to include hydrocarbon-rich parts of a molecule [47]. This type of host is found in the cyclodextrins. [Pg.1002]

The chromatographic separation of enantiomers using CDs is usually performed using aqueous-organic mobile phases. The apparent pH of these... [Pg.1005]

W. H. Pirkle and T. C. Pochapsky, Theory and design of chiral stationary phases for direct chromatographic separation of enantiomers, in K. K. Unger (ed.). Packings and Stationary Phases in Chromatographic Techniques, Marcel Dekker, New York, 1990, p. 783. [Pg.1041]

S. Anderson, S. Allenmark, P. Moller, B. Persson, and D. Sanchez, Chromatographic separation of enantiomers on V,V -diallyl-L-tartardiamide-based network—Polymeric chiral stationary phases, J. Chromatogr. 741 (1996), 23. [Pg.1043]

A. M. Rizzi, Band broadening in high-performance liquid chromatographic separations of enantiomers with swollen microcystalline cellulose triacetate packings. [Pg.1047]


See other pages where Chromatographic Separation of Enantiomers is mentioned: [Pg.129]    [Pg.313]    [Pg.100]    [Pg.271]    [Pg.88]    [Pg.403]    [Pg.569]    [Pg.876]    [Pg.358]    [Pg.129]    [Pg.299]    [Pg.319]    [Pg.265]    [Pg.398]    [Pg.480]    [Pg.137]    [Pg.1045]   


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