Chiral Clusters in a Supersonic Beam: R2PI-TOF Spectroscopy of Diastereomeric Carboxylic Esters/(R)-(+)-1-Phenyl-1-propanol Complexes

Wavelength and mass resolved resonance-enhanced two photon ionization (R2PI) excitation spectra of (R)-(+)-1-phenyl-1-propanol (PR) and its complexes with some chiral esters, i.e. Me lactates (LR and LS), Me 3-hydroxybutyrates (HR and HS), and Me 2-chloropropionates (CR and CS), have been recorded after a supersonic mol. beam expansion and interpreted in the light of DFT calcns. The spectral features of the selected complexes were found to depend on the nature of hydrogen-bond interactions within the diastereomeric complexes, whose intensity in turn depends upon the structure and the configuration of the ester moiety. The study further confirms resonant two-photon ionization spectroscopy, coupled with time-of-flight mass resoln. (R2PI-TOF), as an excellent tool for gathering valuable information on the interactive forces in mol. clusters and for the enantiodiscrimination of chiral mols. in the gas phase.