Investigation of a tartaric acid‐based linear polyamide and dimer as chiral selectors in liquid chromatography

Abstract

A twin selector for enantioselective liquid chromatography based on O,O V-bis(dimethyl)benzoyl tartaric diamide was synthesized and compared to commercially available Kromasil CHI-DMB (O,O V-bis(dimethyl)benzoyl tartaric diamide). A linear polyamide based on the same tartaric acid derivative was also synthesized, immobilized on silica, and evaluated as stationary phase. The twin selector was immobilized as a brush-type phase, with similar bonding chemistry as in Kromasil CHI-DMB. It was shown to exhibit lower resolution power than Kromasil CHI-DMB. However, retention and separation factors obtained on the respective sorbents were shown to exhibit interdependence. CD spectra of the twin selector give no indication that the respective branches interact in the solvent mixtures employed for chromatography. The linear polyamide showed lower enantioselectivity and higher retention than Kromasil CHI-DMB.

The comparison in enantioseparation ability of the chiral stationary phases with single and mixed selector—The selectors derived from two D‐tartrates

“…To improve the enantioseparation ability, some biselector CSPs were reported. [12][13][14][15][16] However, these biselector CSPs do not always show enhanced enantioseparation ability. In the reported works, two chiral compounds were connected with a cross-linker of multiple reactive groups to form a biselector, which was then immobilized on a support to afford a biselector CSP.…”

Investigation of brush‐type chiral stationary phases based on O,O′‐diaroyl tartardiamide and O,O′‐bis‐(arylcarbamoyl) tartardiamide

“…According to reported literatures, Kromasil‐CHI‐DMB could separate the analytes ketoprofen (TR‐29) 11, binaphthol (TR‐1) 11, 12, mephenytoin (TR‐40) 11, methyl N ‐benzoyl‐phenylalaninate (TR‐27) 17 well and had the tendency to resolve benzoin (TR‐34) 12. In this study, on CSP 2 with similar selector, only ketoprofen (TR‐29) could be separated slightly better than Kromasil‐CHI‐DMB.…”

“…Tartaric acid derivatives, such as N , N ′‐diisopropyl‐ L ‐tartardiamide (DIPTA), is a broadly applicable chiral mobile phase additive (CMPA) in silica gel chromatography 8. CSPs of brush type 9, 10 and network copolymer 11–13 based on tartardiamide have been developed successfully to separate a wide variety of racemic solutes under normal‐phase condition. Especially, the chiral columns based on O , O ′‐diaroyl tartardiamide polymer have been commercially available, e.g.…”

Preparation and evaluation of biselector bonded‐type multifunctional chiral stationary phase based on dialdehyde cellulose and 6‐monodeoxy‐6‐monoamino‐β‐cyclodextrine derivatives

“…In general, bonded‐type CSPs have good solvent resistance but show poor enantioseparation ability compared with coated‐type CSPs. To enhance the chiral resolution ability and broaden the scope of chiral recognition, several biselector bonded‐type CSPs have been developed . Chen et al prapared biselector bonded‐type CSP derived from two D‐tartrates, which showed enhanced enantioseparation ability compared with single selector CSPs .…”