Asymmetric compartmental macrocyclic ligands and related mononuclear and hetero-dinuclear complexes with d- and/or f-metal ions

[1 + 1] Asymmetric compartmental macrocycles H2L (H2LA-H2LG), containing on e N2O2, N3O2 or N2O2O2 Schiff base and one adjacent O2O3, O2O4 or O2O5 'cro wn like' coordination chamber, have been prepared by self-condensation or b y reaction of the appropriate diformyl (H2LI-H2LIII) and amine precursors i n the presence of barium(II) salts, followed by a demetallation reaction of the resulting complexes, Ba(H2L)(ClO4)(2), with guanidinium sulphate. They have been characterised by IR, NMR and mass spectrometry. The single cryst al X-ray structural determination of H2LC confirms their [1 + 1] cyclic nat ure. The mononuclear complexes Ln(H2L)(X)(3). nS (Ln = La-Lu; X = Cl-, NO3- ) and Ni(L). nS have been prepared by reaction of the preformed ligands wit h the appropriate metal salt, by template procedure or by condensation of t he acyclic complexes with the diformyl derivatives Ln(H2L')(X)(3) or Ni(L') with the appropriate amine. They have been characterised by IR, NMR, magne tic susceptibility and mass spectrometry. In these mononuclear complexes th e 4f and transition metal ion invariantly occupy respectively, the crown-li ke and the Schiff base chamber. In [La(H2LC)(H2O)(4)]Cl-3 the single crysta l X-ray structure reveals that a bicapped square antiprismatic decacoordina tion about the central metal ion is reached by the coordination of the oxyg en atoms of the crown-ether chamber and by the oxygen atoms of four water m olecules. A Schiff base occupancy has been obtained by the lanthanum ion on ly when Ba(H2L)(ClO4)(2) was used instead of the free ligand H2L: the bariu m ion remains in the crown-ether chamber and obliges the incoming lanthanum ion to fill the Schiff base site. By this procedure the hetero-dinuclear c omplex, LaBa(L-D)(ClO4)(2)(OH). 3H(2)O, has been obtained. La(H2LC)(Cl)(3), by reaction with the appropriate metal salt, gives rise to the hetero-dinu clear species MLa(L-C)(Cl)(2)(OH). nH(2)O (M = Cu, n = 1; M = Ni, n = 2). L aNa(L-D)(X)(2).(X = Cl, NO3) and LaNa(L-F)(NO3)(2) have been synthesised by template procedure or by reaction of H2LD or H2LF with the appropriate lan thanum(III) salt and sodium hydroxide. (C) 1999 Elsevier Science S.A. All r ights reserved.