A STRUCTURAL STUDY OF THE INTERACTION OF DIBENZYLDIAZA-18-CROWN-6 WITH NEODYMIUM(III) NITRATE HEXAHYDRATE

The structure of the complex salt, [C26H40N2O4][Nd(NO3)(5)(H2O)] (1), was determined by single crystal X-ray diffraction. It consists of alt ernating layers of the anionic complex, [Nd(NO3)(5)(H2O)](2-)(,) and t he cationic diprotonated [2H.azacrown] (2+). The Nd3+ complex anion is coordinated to five bidentate nitrate ligands and a water ligand to g ive an 11-coordinated environment. Each Nd moiety is linked to another through intermolecular hydrogen bonding to form pairs of Nd moieties. The azacrown adopts a chair conformation and the benzyl groups are at tached to the nitrogen atoms in an anti position with respect to each other, above and below the plane of the macro-ring in agreement with t he conformation of the uncomplexed protonated azacrown as obtained by the PM3 method. (C) 1998 Elsevier Science B.V. All rights reserved.