Sustainable solutions for direct TLC enantioseparation with in-home thought-out, prepared/modified chiral stationary phases.

Abstract

TLC is used globally, yet less attention has been paid to TLC (in enantioseparation) despite its advantages. The present paper describes/reviews successfully practiced direct approaches of 'chiral additive in achiral stationary phase' (as an application of in-home thought out, prepared, tested, and modified chiral stationary phase), 'pre-mixing of chiral reagent with the enantiomeric mixture' (an approach using both achiral phases during chromatographic separation) and 'chiral additive in mobile phase', and chiral ligand exchange for enantioseparation of DL-amino acids, their derivatives, and some active pharmaceutical ingredients. It provided efficient enantioseparation, quantitative determination, and isolation of native forms via in-situ formation of non-covalent diastereomeric pair. The mechanism of enantioseparation in these approaches has been discussed along with the isolation and establishment of the structure of diastereomers. This may help chemists gain useful insights into fields outside their specialization and the experts get brief accounts of recent key developments, providing solutions for sustainable development of less expensive methods for control of enantiomeric purity and isolation of native enantiomers.