Cellulose tricarbamate

FIGURE 11 Chromatograms of enantiomeric resolution on cellulose tricarbamate CSPs. (a) Econozole. (b) Miconazole, (c) Sulconazole on a Chiralcel OF CSP, with hexane-2-propanol-diethylamine (425 74 1, v/v/v) as the mobile phase, (d) ( )-f/ reoMethyl-phenidate on a Chiralcel OD CSP, with hexane-ethanol-methanol-trifluoroacetic acid (480 9.75 9.75 0.5, v/v/v/v) as the mobile phase. (From Refs. 100, 101.)... 

In Chapter 4, the authors discuss the noncommercial CSPs, their preparation, and the in-laboratory preparation (home coating) of the chromatographic plates by using these sorbents. Among the stationary phases discussed are cellulose, cellulose triacetate, cellulose tribenzoate, cellulose tricarbamate molecular imprinting polymers (MIPs), and jS-cyclodextrin ( -CD) bonded to the silica gel matrix. 

Preparation of Cellulose Tricarbamate Derivatives and Noncommercial Plates... 

Conventionally produced cellulose powders (microcrystalline cellulose) consist of irregularly shaped fibrous particles of limited use for column chromatography. Beaded cellulose is prepared by dissolution of cellulose powder in a suitable solvent, followed by droplet formation in a suspension medium, and subsequent solvent extraction or crosslinking. Cellulose triacetate and tricarbamate derivatives are useful as low-cost sorbents for the process-scale separation of enantiomers (section 10.4.2). 

In CSPs, owing to the nature of the polymer structure, the simultaneous participation of several chiral sites or several polymer chains is conceivable. In CCSPs, the chiral sites are distributed on the surface or in the network of the achiral matrix relatively far away from each other, and only bimolecular interaction is generally possible with the optical antipodes. A survey of the optically active substance classes separated with Chiral plate and HPTLC Chir layers and with microcrystalline cellulose triacetate (MCTA) plates is shown in Fig. 1. Cellulose tribenzoate and tricarbamate have recently been used for the separation of enantiomeric aromatic alcohols, Troger s base, and benzoin ethyl ether. 

Some chromatograms showing the best resolutions obtained on layers of cellulose and amylose tricarbamates (a, b, and c) at different eluent compositions were... 

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