The role of intramolecular hydrogen bonding in photoelectron circular dichroism: the diastereoisomers of 1-amino-2-indanol

Abstract

(1R,2R)-trans-Aminoindanol and (1S,2R)-cis-aminoindanol, denoted as trans-AI and cis-AI, are diastereoisomer aromatic aminoalcohols differing by the presence of a weak intramolecular hydrogen bond in cis-AI, which is absent in trans-AI. They also differ by the number of conformers under supersonic jet conditions, one for trans-AI and two for cis-AI. One-photon and resonance-enhanced two-photon photoelectron circular dichroism (PECD) spectra are obtained for the two molecules. One-photon ionisation above 11 eV results in molecular fragmentation, with very similar fragmentation pathways for trans-AI and cis-AI. Identical PECD spectra for different fragments allow associating them with reactions occurring from the same parent ion within the same electronic state. The shape of the PECD spectra is sensitive to configuration, conformation, and intramolecular hydrogen bonding. Two-photon PECD, being conformer specific, shows that the PECDs of the two ring-puckering conformers of cis-AI have identical signs but different values.