SYNTHESIS, CHARACTERIZATION AND CRYSTAL-STRUCTURES OF COMPLEXES OF SODIUM HEXAFLUOROPHOSPHATE WITH DIBENZO-18-CROWN-6 AND DIBENZO-24-CROWN-8 MACROCYCLES

Crown ether complexes formed by sodium hexafluorophosphate with dibenz o-18-crown-6 (DB 18C6) and dibenzo-24-crown-g (DB24C8) were synthesize d and their crystal structures determined by single crystal X-ray anal yses. The complex with DB18C6 consists of [Na(DB18C6) (H2O)](+) cation s, free DB18C6 ligand and PF6- anions (compound 1). The sodium cation interacts with the six oxygen atoms of the crown ether and with the ox ygen atom of the water molecule, which forms short contacts also with the free DB18C6 molecule. The compound with DB24C8 (compound 2) consis ts of [Na(DB24C8)](+) cations and PF6- anions. The sodium atom is link ed to the eight oxygen atoms of the DB24C8 macrocycle, whereas the flu orine atoms of the hexafluorophosphate anions do not interact with the sodium atom. (C) 1998 Elsevier Science S.A. All rights reserved.