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Cinchona industrial applications

For the hydrogenation of a-keto esters and a-keto acetals, the performance of the heterogeneous cinchona-modified Pt catalysts is equal to and in some cases superior to the best homogenous catalysts. Indeed, several industrial applications have been described that underline this statement. For most other substrates, the performance of the cinchona-modified Pd or Pt catalysts is not (yet) on a level where the application to real-world substrates has been demonstrated. [Pg.26]

This multiauthor handbook will cover the whole spectrum of cinchona alkaloid chemistry ranging from the fundamentals to industrial applications. This book is organized in four units, namely, the use of cinchona alkaloids as chirality inducers in metal-promoted reactions (Chapters 2-4), the use of cinchona alkaloids as chiral organocatalysts (Chapters 5-11), the organic chemistry of cinchona alkaloids themselves (Chapter 12), and the use of cinchona alkaloids as chiral discriminating agents... [Pg.557]

A notable change in methods of isolating alkaloids from plant materials has been described by Applezweig, depending on the use of a suitable ion-exchange material and capable of application on a semi-micro scale or for industrial use. It has been applied to the preparation of the total alkaloids of cinchona bark (totaquina) and according to Sussman, Mindler and Wood, is also used industrially for the recovery of hyoscine. [Pg.821]

Meanwhile, a wide variety of cinchona alkaloid derivatives have been systematically developed as chiral selectors, which complement each other in their enantiomer discrimination profiles. Considering the variety of derivatives, an overall reasonably broad applicability spectrum, approximating for chiral acids a 100% success rate, is yielded and extreme enantiorecognition levels (a-values above 15) could be realized for some chiral solutes with certain selectors. Moreover, various studies carried out with the CHIRALPAK QD/QN-AX columns in industry and academia clearly document their practical usefulness for solving challenging real-life problems and this should be illustrated by the present review article as well. [Pg.7]

With capillary electrophoresis (CE), another modern primarily analytically oriented separation methodology has recently found its way into routine and research laboratories of the pharmaceutical industries. As the most beneficial characteristics over HPLC separations the extremely high efficiency leading to enhanced peak capacities and often better detectability of minor impurities, complementary selectivity profiles to HPLC due to a different separation mechanism as well as the capability to perform separations faster than by HPLC are frequently encountered as the most prominent advantages. On the negative side, there have to be mentioned detection sensitivity limitations due to the short path length of on-capillary UV detection, less robust methods, and occasionally problems with run-to-run repeatability. Nevertheless, CE assays have now been adopted by industrial labs as well and this holds in particular for enantiomer separations of chiral pharmaceuticals. While native cyclodextrins and their derivatives, respectively, are commonly employed as chiral additives to the BGEs to create mobility differences for the distinct enantiomers in the electric field, it could be demonstrated that cinchona alkaloids [128-130] and in particular their derivatives are applicable selectors for CE enantiomer separation of chiral acids [19,66,119,131-136]. [Pg.87]

The cinchona-catalyzed alcoholysis of meso-anhydrides has been successfully applied to the synthesis of key intermediates for a variety of industrially interesting biologically active compounds. Some selected examples are summarized in Scheme 11.13. More detailed information on the synthetic application of this reaction is available in the recent comprehensive review of this topic by Bolm et al. [la]. [Pg.336]

Phase-transfer catalysis is one of the most practical synthetic methodologies because of its operational simplicity and mild reaction conditions, which enable applications in industrial syntheses as a sustainable green chemical process. As reviewed in this chapter, diverse Cinchona alkaloid-derived quaternaiy ammonium salts have been developed via the modification of Cinchona alkaloids based on steric or electronic factors as highly efficient chiral PTC catalysts and successfully applied in various asymmetric organic reactions. Despite the successful development and application of these catalysts, some problems remain to be addressed. Although Cinchona alkaloids have unique structural features, resulting in the availability of four... [Pg.129]

Broad application of Cinchona alkaloids in medicine, food industry, as well as in academic research has stimulated very early the development of both qualitative and quantitative methods for their analysis. Currently, chromatographic TLC [98, 99], HPTLC [99, 100], HPLC [76, 101-104], and LC-MS [105, 106] and electrochromatographic methods [107] are preferred for Cinchona alkaloid separation, identification, and quantitative analysis. Older analytics from this field is the subject of a review [23]. [Pg.615]


See other pages where Cinchona industrial applications is mentioned: [Pg.335]    [Pg.101]    [Pg.469]    [Pg.461]    [Pg.68]    [Pg.345]    [Pg.14]    [Pg.121]    [Pg.330]    [Pg.424]    [Pg.424]    [Pg.6]    [Pg.1]   
See also in sourсe #XX -- [ Pg.128 , Pg.420 ]

See also in sourсe #XX -- [ Pg.1375 ]




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