METAL ALPHA,OMEGA DICARBOXYLATE COMPLEXES .3. SYNTHESIS, CHARACTERIZATION AND SINGLE-CRYSTAL X-RAY-INVESTIGATION OF AKIS(2-METHYLIMIDAZOLO)(MU-DIADIPATO)DICOBALT(II)] MONOHYDRATE

Interaction of a-methyl imidazole with tetraaquoadipatocobalt(II) poly mer in water-ethanol mixture yielded dimeric cobalt(II) complex[Co(COO -(CH2)(4)-COO) (C4N2H6)(2)]. H2O. The complex has been characterized b y elemental analysis, IR spectroscopy and single crystal X-ray diffrac tion techniques. The crystal structure contains a dimer consisting of two Co(cis-2Melm) units joined by two-molecules of a folded dibasic ac id forming an 18 membered ring. The metal center possesses a highly di storted octahedral geometry comprising two N-atoms from two 2-methylim idazoles and four O-atoms form two adipate anions forming strained fou r membered chelate rings. The molecule has a center of symmetry and fo rms a through channel with the maximum and minimum dimensions of 8.25( 7) Angstrom and 5.27(2) Angstrom respectively. The hexagonally close p acked dimeric units along a-axis includes a water molecule in the exte rior channel. (C) 1997 Elsevier Science Ltd.