Planar chromatography scope

Additional details of planar chromatography—methods of descending and radial development, how to prepare TLC plates, tips on how to apply the sample, what to do if the spots are not visible—and the details of preparatory TLC, etc., are beyond our scope. 

R Scopes, Protein Purification Principles and Practice, 3rd ed (1993), Spnnger-Verlag (Berlin). Introduction to all methods of chromatography J Sherma, Anal. Chem. 62, 371R-381R (1990) Planar Chromatography. ... 

The book comprises 19 chapters that are divided into Sections I and II. Section I contains Chapters 1 through 9, which provide an overview of chromatographic thin layers, special instrumentation for the TLC-MS coupling, and various different mass spectrometric techniques that can be directly or indirectly combined into the planar chromatography-MS methodologies. Gel electrophoretic layers are additionally included in this book because they formally fall within the scope of the definition of a thin layer and can be coupled offline with mass spectrometric detectors. Section II... 

SCOPE OF ULTRATHIN-LAYER CHROMATOGRAPHY-MASS SPECTROMETRY LAYERS INTRODUCTION TO MINIATURIZED PLANAR CHROMATOGRAPHY... 

Kaiser, R. (1988). Scope and limitations of modern planar chromatography—sampling. 

Kaiser, R. E. (1988). Scope and limitations of modern planar chromatography. Part 2 Separation modes. J. Planar Chromatogr.—Mod. TLC 1 265-268. 

We have purposely narrowed the scope of all multidimensional chromatography to those techniques that incorporate separations in the liquid phase and to those in which the use of the comprehensive mode prevails but is not exclusive. This text neither incorporates elements of multidimensional thin-layer chromatography, multidimensional separations in gel media such as those commonly employed for the separation of complex mixtures of proteins, nor the techniques that utilize multidimensional gas chromatography. Some of the same principles apply, particularly in the theory section, but our emphasis is strictly on separations carried out in the liquid phase and by columns, rather than in the gas phase or in planar configurations. 

Substituted [2.2]paracyclophane compounds exhibit planar chirality [3, 4]. In contrast to conformationally flexible chiral molecules with an axis of rotation and a rotatable bond around a stereogenic center, the planar chirahty of [2.2]paracyclo-phane compounds possesses a conformationally stable chiral space because of the fixed aromatic rings. From this structural viewpoint, various methods for the optical resolution of planar chiral [2.2]paracyclophanes have been developed since the 1990s [79-92]. In comparison with the establishment of the optical resolution of monosubstituted [2.2]paracyclophanes, there was more scope for the development of optical resolution of pseudo-ortfio-disubstituted [2.2]paracyclophanes [85-92]. Recently, a simple optical resolution method for racemic pseudo-ort/to-dibromo[2.2] paracyclophane rac-38 was reported [93]. As shown in Scheme 11, treatment of rac-38 with a slight excess of n-BuLi and (lR,25,5R)-(-)-menthyl S)-p-toluenesulflnate provided a mixture of diastereomers (Rp,5)-42 and (5p,5)-42. These were readily separated by conventional Si02 column chromatography to afford (Rp,S)-42 and (5p,5)-42 (each in 39 % isolated yield). 

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