Self-disproportionation of enantiomers of 3,3,3-trifluorolactic acid amides via sublimation

Self‐disproportionation of Enantiomers (SDE) of Chiral Nonracemic Amides via Achiral Chromatography

“…In this regard, fractional crystallization, arising from the differences in solubility, is anything but unique, as any other differences in the physicochemical properties can be used for the purpose of enantiomeric purification. For example, SDE via density gradient centrifugation or SDE via sublimation, are far much less known, but can be quite successfully used for practical enantiomeric purifications . Similarly to the distinct crystallographic structures observed in the solid state, chiral compounds in the liquid state or in solution show well‐defined preferences for homochiral/heterochiral dynamic molecular associations, accounting for various nonlinear effects, including SDE via chromatography ,,.…”

Optical Purifications via Self‐Disproportionation of Enantiomers by Achiral Chromatography: Case Study of a Series of α‐CF3‐containing Secondary Alcohols

“…1 Furthermore, it is generally accepted practice that the analytical data reported in the literature for chiral compounds are measured on samples as they are obtained by asymmetric reactions without further purification to enantiomerically pure state. In this context, one of the promising areas is the self-disproportionation of enantiomers (SDE) [3][4][5][6] demonstrating that optical purification of enantiomerically enriched compounds via separation of racemate from the excess enantiomer †7 can be achieved under achiral conditions of any type of phase-transition [8][9][10][11][12][13][14][15][16][17][18][19][20] or achiral chromatography. 2 Apparently, the major reason for reporting chiral compounds of various enantiomeric purities, is the painstaking, expensive and time-consuming efforts usually associated with the purification of enantiomerically enriched samples to optically pure form.…”

Enantiomer self‐disproportionation and chiral stationary phase based selective chiral separation of organic compounds

“…Therefore, purification, analysis, and application of chiral isomers have been the most active subject of investigation in chemical industry as well as in academic research, as its enantiomeric purity is a major concern. 4,5 Conventionally, different methods such as chiral pool, enzymatic separation, separation through resolving agent, asymmetric catalysis, chiral chromatography, fractional sublimation of non-racemic compounds, [6][7][8] and ESD have been used to acquire enantiomerically pure compounds. Still it is necessary to improve a few economical and environmental aspects such as (a) chiral pool is based on natural resources only; (b) enzymatic separation provides one form of isomer; (c) resolving agent is required in huge amount to attain the desired yield; (d) separation of product from catalyst is difficult in asymmetric catalysis, and it leads to the degradation of an expensive catalyst.…”