Pasteur-like resolution of quasi-racemates in solid and gas phases

Abstract

Isotopomeric quasi-racemates (IQR), i.e., 1:1 mixtures of enantiomers one of which contains an isotopic label, can undergo crystallisation as conglomerates or true quasi-racemates. In the former case, each single crystal contains, predominantly or exclusively, either labelled or non-labelled enantiomers, whereas in the latter case, it contains both enantiomers (1:1). If solution sputtering is used to ionise quasi-racemates, the formation of homochiral protonated and metallated enantiomers and their homo-chiral oligomers in the gas phase is detected in ion cyclotron resonance (ICR) mass spectra; these compounds differ in their m/z values; hence, Pasteur-like 'manual sorting' can be employed to catch them successively in the ion trap of the spectrometer.