Beta-blocker conformations in the gas phase: 2-phenoxy ethylamine, its hydrated clusters and 3-phenoxy propanolamine

Abstract

The molecular conformation and structure of 2-phenoxy ethylamine and its hydrated complexes and of the generic β-blocker molecule, 3-phenoxy propanolamine have been investigated and assigned using a combination of mass-selected, resonant two-photon ionisation (R2PI), coupled with infrared ion-dip spectroscopy and ab initio calculations. The results are compared with recent investigations of 2-phenoxy ethanol, 2-phenyl ethanolamine, the ephedra and noradrenaline. Attention is focused particularly on the degree of hydrogen bonding and rigidity or flexibility in the side chain and on the organisation and structural influence of bound water molecules.