Spontaneous resolution in racemic solutions of N-trifluoroacetylated α-aminoalcohols

Abstract N-trifluoroacetylated α -aminoalcohol are low molecular weight (Mw ∼200 Da) gelators. Under cooling of the homochiral solutions, TFAAAs form highly elongated supramolecular structures (strings). In the racemic solution of TFAAA-6 in CCl 4 , we observed spontaneous resolution of enantiomers and formation of the conglomerate composed of the highly elongated strings. Herewith, in the racemic solution of TFAAA-5 in heptane, the spontaneous resolution was not observed, and we found the isometric precipitate instead of the strings. At the same time, in the TFAAA-5 solutions with small enantiomeric excess (EE), the homochiral strings were observed along with the isometric precipitate. In this case, the strings were formed from the excess of one of the enantiomers that remained in solution after precipitation of the racemic residual. This process leads to the enhancement of chiral polarization in systems close to racemic and can explain the chiral purity of the living cell.