PREPARATION, PROPERTIES AND COORDINATION BEHAVIOR OF PLANAR OR TRIDIMENSIONAL COMPARTMENTAL SCHIFF-BASES

Planar compartmental Schiff bases containing an inner N2O2 or N3O2 and an outer 0202 chamber were prepared by condensation of 3-methoxysalic ylaldehyde with 1,2-diaminoethane (H2L(A)) or 4-N-dodecyldiethylenetri amine (H2L(B)). Mononuclear and homodinuclear complexes were synthesiz ed by reaction of the ligands with metal salts or by template procedur e; heterodinuclear complexes were obtained by step by step reactions. Tridimensional compartmental ligands, containing an inner N4O3 and an outer 0303 chamber, obtained by condensation of tris(2-ethylamine)amin e with 3-methoxy- (H3L(C)) or 3-hydroxysalicylaldehyde (H6L(D)) form w ith M(CH3COO)2.nH2O (M=Mn2+, Fe2+) the mononuclear iron(III) and manga nese(III) complexes, M(L(C)) or M(H3L(D)). In these complexes the oxid ation of the central metal ion occurs as ascertained by Mossbauer and X-ray structural determinations. The crystal molecular structure of th e manganese(III) complex, MnL(C) was established by X-ray diffraction methods. This complex crystallizes in the monoclinic system, space gro up P2(1)/c in a cell of dimensions a=10.910(4), b=12.382(4), c=21.196( 6) angstrom and beta=90.91(6)-degrees, with Z=4. The structure was ref ined to the conventional agreement index R=0.057 with 1880 observed re flections. The manganese(III) ion coordinates in the inner chamber, gi ving rise to an octahedral complex with the N3O3 donor set formed by t he phenolate oxygen and the imine nitrogen donor atoms. The apical ami ne nitrogen is not involved in the coordination. Bond lengths in the o ctahedral coordination polyhedron are comprised between 1.897(5) and 2 .081(6) angstrom for the three oxygens and 2.075(7) and 2.317(7) angst rom for the three nitrogen donors to the metal ion. The possibility of using this manganese(III) complex (MnL(C)) as a ligand towards Ln(X)3 , or KBr has also been studied.