Chiral packing materials

Okamoto, Y., Kawashima, M., Yamamoto, K., and Hatada, K. (1984) Useful chiral packing materials for high-performance liquid chromatographic resolution. Cellulose triacetate and tribenzoate coated on macroporous silica gel, Chem. Lett., 739-742. 

Y. Okamoto, M. Kawashima, and K. Hatada, Chromatographic resolution. 7. Useful chiral packing materials for high-performance hquid chromatographic resolution of enantiomers Phenylcarbamates of polysaccharides coated on sihca gel, J. Am. Chem. Soc. 106 (1984), 5357-5359. 

The classical method for separating enantiomers is to form diastereomeric compounds using a stoichiometric amount of a resolving agent. This method was described in Section 2.1.8. In this section, we discuss methods of resolution based on physical separations, including chromatography with chiral packing materials and capillary electrophoresis. 

One important type of chiral packing material is derivatized polysaccharides, which provide a chiral lattice, but separation is improved by the addition of structural features that enhance selectivity. One group of compounds includes aroyl esters and carbamates, which are called Chiralcels (also spelled Chiracel) two of the most important examples are the 4-methylbenzoyl ester, called Chiralcel OJ, and the 3,5-dimethylphenyl carbamate, called Chiralcel OD. There is a related series of materials derived from amylose rather than cellulose, which have the trade name Chiralpak. 

Ikai, T., Yamamoto, C., Kamigaito, M., and Okamoto, Y. (2008) Immobilized-type chiral packing materials for HPLC based... 

A common method for resolving enantiomers today is chromatography using a chiral packing material in the column. Each enantiomer in principle interacts differently with the chiral packing material, and the elution time will be different for each enantiomer. A wide variety of chiral column packing materials have been developed for this purpose. 

Shen J, Liua S, Li P, Shen X, Okamoto Y (2012) Controlled synthesis and chiral recognition of immobilized cellulose and amylose tris(cyclohexylcarbamate)s/3-(triethoxysilyl)propylcarbamates as chiral packing materials for high-performance liquid chromatography. J Chromatogr A 1246 137-144... 

Ikai T, Yamamoto C, Kamigaito M, Okamoto Y (2007) Immobilization of polysaccharide derivatives onto silica gel Facile synthesis of chiral packing materials by means of intermo-lecular polycondensation of triethoxysilyl groups. J Chromatogr A 1157 151-158... 

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