Stationary phases amylose, preparation

The Preparation of the Pirkle Stationary Phases The Preparation of Cellulose and Amylose Stationary Phases The Preparation of the Macrocyclic Glycopeptides Phases The Preparation of the Cyclodextrin Based Stationary Phases Column Packing Techniques... 

The majority of preparative separations undertaken at Ultrafine have used chiral stationary phases based on either cellulose or amylose derivatives. In one project 500 mg of salts of both the (R,R)- and (S,S)-Formoterol (6) enantiomers were prepared using an OJ column with a resulting ee of >97%.45 A loading of 200 mg/mL on a semipreparative column was achievable without loss of resolution or purity relative to the racemate. 

Advances in preparative enantioseparation by simulated moving bed (SMB) chromatography have occurred in the last 10 years. SMB was invented in the 1960s and was used by the petrochemical and sugar industries. Now with the improvements in stationary phases and hardware it is an option for the large-scale preparation of enantiomerically pure material. The majority of the latest published data are using either amylose- or cellulose-based phases because of their selectivity. There are now examples in the literature of the commercial separation on the multi-ton scale.8... 

The ester and carbamate derivatives of cellulose and amylose are among the most successful and versatile chiral stationary phases for liquid and supercritical fluid chromatography [1,4,28,107-109]. These phases are prepared by reaction of the poly(saccharide) with an acid chloride (ester derivative) or phenylisocyanate (carbamate... 

After the first patents of the coated cellulose- and amylose-type CSPs expired in 2006 a series of generic CSPs have been introduced into the market. The main arguments for choosing one of these phases for a preparative separation process should be the loadability and stability of the stationary phase beside the price per... 

Recently, Kubota et al. [37] prepared cyclohexylcarbamates of cellulose and amylose to evaluate their chiral recognition abilities as stationary phases for HPLC and TLC. 

Preparation of the stationary phase was performed by dissolving 0.75 g of amylose tnXcyclohexyl carbamate) in 10 ml of tetrahydrofuran. Macroporous silanized silica gel (3 g) [made from silica gel, Daiso Gel SP-1000, pore size 100 nm, particle size 7 /u-m, silanized using (3-aminopropyl)triethoxysilane in benzene at 80°C] was added to the solution and the resulting suspension was dried under vacuum. A portion of this material (1.5 g) and fluorescent indicator (Merck) (0.1 g) were mixed with methanol (3 ml). The slurry was applied to microslides (2.6 X 7.6 cm, thickness 0.3 mm) and the plates were dried in an oven at 110°C for 30 min [37]. 

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