Cellulose phenylcarbamates

Cellulose triacetate Cellulose tribenzoate Cellulose mew-methylbcnzoate Cellulose para-methylbenzoate Cellulose phenylcarbamate... 

The chiral recognition ability of a series of cellulose phenylcarbamate derivatives has been evaluated extensively [18,43]. The introduction of an electron-donating methyl group or an electron-withdrawing halogen at the 3-and/or 4-position improved the resolution ability, but substituents at position 2 showed poor chiral resolution capacity. The derivatives with heteroatom substi-... 

Yashima, E., Yamamoto, C., and Okamoto, Y. (1996) NMR studies of chiral discrimination relevant to the liquid chromatographic enantioseparation by a cellulose phenylcarbamate derivative, J. Am. Chem. Soc. 118, 4036-4048. 

Fig. 8 Plots of retention times t of (a) acetone and (b) the first enantiomer of 16 to elute on cellulose phenylcarbamate derivatives against the Hammett parameter a of the substituents. Reprinted by permission from Elsevier [20]...

Cellulose phenylcarbamate derivatives (Figures 4.4a,b) showed high a-values but low 7 s-values because of the elongated spots. In particular, f ,5-propranolol (Figure 4.4a) yielded a = 5.5 and Rs near the unity, whereas bupranolol (Figure 4.4b) showed a = 2.53 and / s-value approaching the unity. 

The use of microcrystalline cellulose and cellulose phenylcarbamate mixtures in the ratio 1 1 (w/w) involved a better adherence of the stationary phase to the glass microslide, and a better visualization of solutes. 

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