Howell, Robertha C.; Edwards, S.H.; Gajadhar-Plummer, A.S.; Kahwa, Ishenkumba A.; McPherson, G.L.; Mague, J.T.; White, A.J.P.; Williams, D.J.
Author Affiliation, Ana.
Department of Chemistry
Phthalimides: Supramolecular interactions in crystals, hypersensitive solution H-1-NMR dynamics and energy transfer to europium(III) and terbium(III) states
Date of Publication
Detailed crystal structures and H-1-NMR characteristics of some alkylaminephthalimides, including dendritic polyphthalimides, are reported. These investigations were undertaken in order to obtain a better understanding of the relationship between solid-state supramolecular interactions, their persistence in solution and associated dynamics of magnetically hypersensitive phthalimide aromatic AA'BB'-AA'XX' proton NMR resonances. Some alkylamine phthalimides feature folded molecular geometries, which we attribute to n-pi interactions among proximal amine-phthalimide sites; those alkylamine-phthalimides that have no possibility for such interactions feature fully extended phthalimide functionalities. Accordingly, alkylamine phthalimide compounds with folded solid-state geometries feature solvent and temperature dependent hypersensitive AA'BB'-AA'XX' H-1-NMR line profiles, which we attribute to the n-pi interactions. Luminescence of Eu3+(D-5(o)) and Tb3+(D-5(4)) states show well defined metal ion environments in their complexes with dendritic phthalimides, as well as relatively weak phthalimide-lanthanide(III) interactions.....