Horning-crown diamine complexes and salts: proton transfer mediated by solid-state intermolecular hydrogen bondingCCDC reference numbers 767013, 767014, and 641524-641527. For crystallographic data in CIF or other electronic format see DOI: 10.1039/c003571h

Horning-crownmacrocycles form sheath/core inclusion complexes or salts with alkyldiamines. The degree of proton transfer appears to be mediated by intermolecular hydrogen bonding interactions. Among seven crystal structures examined, neutral complexes, hemi-salts and salts were revealed. With crystalline materials, the extent of proton transfer appeared to reflect the degree of stabilisation of phenolates and ammoniumgroups by hydrogen bond donors and acceptors rather than merely differences in solution phase p K a . Horning-crowns formed sheath/core inclusion complexes, hemi-salts or salts with alkyldiamines. Proton transfer in these crystalline complexes reflected the degree of stabilisation of phenolates and ammonium groups by hydrogen bond donors and acceptors rather than differences in solution phase p K a .