Racemization by chromatographic column

31 July 2017 1 3K Report

Using chiral b-dex column and commercial R-oxide-styrene patterns for separation of epoxides in GC, 2 peaks are shown, the stationary phase is 2,3-di-O-methyl-6-0-TBDMS-β-cyclodextrin, The conditions of the method are: pressure about 10 psi, temperature from 50 to 220 ° C, 2.5 degrees per min, injector 300 ° C detector 300 ° C. Why is racemization generated?

Bruce Neagle

Because high temperatures common in the GC will open the ring and rotate the carbon bonds so you obtain racemization.

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