Chiraldex capillary columns

TABLE 3.15 General Classes of Compounds Separated on Selected Chiraldex Capillary Columns... 

Chiraldex Capillary GC Columns Chiral Separations. ASTEC, 37 Leslie Court, P.O. Box 297, Whippany, NJ 07981. 

Hydrolytic Kinetic Resolution (HKR) of epichlorohydrin. The HKR reaction was performed by the standard procedure as reported by us earlier (17, 22). After the completion of the HKR reaction, all of the reaction products were removed by evacuation (epoxide was removed at room temperature ( 300 K) and diol was removed at a temperature of 323-329 K). The recovered catalyst was then recycled up to three times in the HKR reaction. For flow experiments, a mixture of racemic epichlorohydrin (600 mmol), water (0.7 eq., 7.56 ml) and chlorobenzene (7.2 ml) in isopropyl alcohol (600 mmol) as the co-solvent was pumped across a 12 cm long stainless steel fixed bed reactor containing SBA-15 Co-OAc salen catalyst (B) bed ( 297 mg) via syringe pump at a flow rate of 35 p,l/min. Approximately 10 cm of the reactor inlet was filled with glass beads and a 2 pm stainless steel frit was installed at the outlet of the reactor. Reaction products were analyzed by gas chromatography using ChiralDex GTA capillary column and an FID detector. 

HP5890 Series II Gas Chromatograph equipped with a chiraldex G-TA capillary column and a flame ionization detector... 

The conversion of acetophenone to acetophenone cyanohydrin and enantiomeric excess were determined by gas chromatographic analysis after product derivatisation as the trifluoroacetate. GC was performed using a Chiraldex capillary GC column (G-PN -y-Cyclodextrin, Propionyl) from Astec using a CP3800 (Varian) with a flame ionization detector. Carrier gas was helium at 2 mL min . Temperature gradient 80 °C for 0.5 min, raise at 10.8°C min to 130 °C and hold 130 °C for 15 min. The injector and detector temperamres were set to 250 °C. 

Chiraldex Capillary GC Columns A Guide to Using Cyclodextrin Bonded Phases for Gas Chromatography Advanced Separation Technologies, Inc., 1990. 

Separation Technologies Inc., of Whippany, NJ, USA. In 1991, the same company received two global patents for the use of two specific cyclodextrin derivatives for the separation of enantiomers by capillary GC. This technology is known by the trade name of Chiraldex. Various Chiraldex columns have been developed, using the prefixes A, B and G for the a-, and y-CDs, respectively [92], Similarly, Supelco have also developed various chiral stationary phases under the trade name of Dex a-Dex, S-Dex and y-Dex CSPs on fused silica capillary columns containing premethylated a-, and y-CDs coupled to a phenyl that contains a stationary polysiloxane... 

The epoxide and aldehyde were identified and quantified by capillary GLC equipped with a Chiraldex G-TA column using 4-bromochloroben-zene as the internal standard (oven temp 110 °C, carrier gas He, flow rate 60-65mL min-1, split ratio 100 1, detector FID at 250 °C, (IS, 2S)-(E)- -methylstyrene oxide Rt = 6.98min (1R, 2R)-( )-(3-methylstyrene oxide Rt = 7.81 min.) The enantiopurity of the //L2R-epoxide = 70% ee, Yield = 90 % (>99 % trans). 

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